monoxide: an oxide containing just one atom of oxygen in the molecule


montan wax: a hard wax obtained from lignite


moonstone: a transparent or translucent gemstone with a pearly luster; some specimens are orthoclase feldspar and others are plagioclase feldspar


mordant: a substance used to treat leather or other materials before dyeing; aids in dyeing process


chrome alum: a violet-colored salt used in hide tanning and as a mordant in dyeing


tartar emetic: a poisonous colorless salt used as a mordant and in medicine


antimony potassium tartrate: a poisonous colorless salt used as a mordant and in medicine


tartrate: a salt or ester of tartaric acid


bitartrate: an acid tartrate; a hydrogen tartrate


morganite: a kind of pink beryl used as a gemstone


mortar: used as a bond in masonry or for covering a wall


mucoid: any of several glycoproteins similar to mucin


mucopolysaccharide: complex polysaccharides containing an amino group; occur chiefly as components of connective tissue


mud: water soaked soil; soft wet earth


clay: water soaked soil; soft wet earth


slop: deep soft mud in water or slush


mire: deep soft mud in water or slush


sludge: any thick, viscous matter


slime: any thick, viscous matter


goo: any thick, viscous matter


goop: any thick, viscous matter


gook: any thick, viscous matter


guck: any thick, viscous matter


gunk: any thick, viscous matter


muck: any thick, viscous matter


ooze: any thick, viscous matter


sapropel: sludge (rich in organic matter) that accumulates at the bottom of lakes or oceans


muriatic acid: a former name for hydrochloric acid


music paper: paper with lines appropriate for writing music


score paper: paper with lines appropriate for writing music


mustard gas: a toxic war gas with sulfide based compounds that raises blisters and attacks the eyes and lungs; there is no known antidote


mustard agent: a toxic war gas with sulfide based compounds that raises blisters and attacks the eyes and lungs; there is no known antidote


blistering agent: a toxic war gas with sulfide based compounds that raises blisters and attacks the eyes and lungs; there is no known antidote


dichloroethyl sulfide: a toxic war gas with sulfide based compounds that raises blisters and attacks the eyes and lungs; there is no known antidote


sulfur mustard: a toxic war gas with sulfide based compounds that raises blisters and attacks the eyes and lungs; there is no known antidote


muton: the smallest unit of DNA where a mutation can occur


nitrogen mustard: a toxic compound resembling mustard gas in structure; important in cancer treatment


mutton tallow: tallow from the body of a mature sheep


myelin: a white fatty substance that forms a medullary sheath around the axis cylinder of some nerve fibers


myeline: a white fatty substance that forms a medullary sheath around the axis cylinder of some nerve fibers


medulla: a white fatty substance that forms a medullary sheath around the axis cylinder of some nerve fibers


myristic acid: a saturated fatty acid occurring naturally in animal and vegetable fats


tetradecanoic acid: a saturated fatty acid occurring naturally in animal and vegetable fats


napalm: gasoline jelled with aluminum soaps; highly incendiary liquid used in fire bombs and flamethrowers


naphtha: any of various volatile flammable liquid hydrocarbon mixtures; used chiefly as solvents


naphthalene: a white crystalline strong-smelling hydrocarbon made from coal tar or petroleum and used in organic synthesis and as a fumigant in mothballs


naphthol: either of two phenols derived from naphthalene


pyrene: a pale yellow crystalline hydrocarbon C16H10 extracted from coal tar


man-made fiber: fiber created from natural materials or by chemical processes


synthetic fiber: fiber created from natural materials or by chemical processes


natural fiber: fiber derived from plants or animals


natural fibre: fiber derived from plants or animals


animal fiber: fiber derived from animals


animal fibre: fiber derived from animals


plant fiber: fiber derived from plants


plant fibre: fiber derived from plants


straw: plant fiber used e.g. for making baskets and hats or as fodder


natural gas: a fossil fuel in the gaseous state; used for cooking and heating homes


gas: a fossil fuel in the gaseous state; used for cooking and heating homes


naval brass: alpha-beta brass containing tin; resistant to sea water; Admiralty Metal is a trademark


Admiralty brass: alpha-beta brass containing tin; resistant to sea water; Admiralty Metal is a trademark


Admiralty Metal: alpha-beta brass containing tin; resistant to sea water; Admiralty Metal is a trademark


Tobin bronze: alpha-beta brass containing tin; resistant to sea water; Admiralty Metal is a trademark


neat's-foot oil: a pale yellow oil made from the feet and legs of cattle; used as a dressing for leather


nebula: a medicinal liquid preparation intended for use in an atomizer


nerve gas: a toxic gas that is inhaled or absorbed through the skin and has harmful effects on the nervous and respiratory system


nerve agent: a toxic gas that is inhaled or absorbed through the skin and has harmful effects on the nervous and respiratory system


VX gas: a highly lethal nerve agent used in chemical warfare; a toxic liquid that penetrates the skin or lungs to disrupt the nervous system and stop respiration; in combat VX gas is deployed by detonating a container over the target area and can persist in the environment up to several weeks after release


sarin: a highly toxic chemical nerve agent that inhibits the activity of cholinesterase


GB: a highly toxic chemical nerve agent that inhibits the activity of cholinesterase


neuromuscular blocking agent: a substance that interferes with the neural transmission between motor neurons and skeletal muscles


newspaper: cheap paper made from wood pulp and used for printing newspapers


newsprint: cheap paper made from wood pulp and used for printing newspapers


Nichrome: an alloy of nickel and chromium with high electrical resistance and an ability to withstand high temperatures; used for resistance heating elements


nickel-base alloy: an alloy whose main constituent is nickel


nickel alloy: an alloy whose main constituent is nickel


nickel bronze: a bronze containing up to 30% nickel


nickel silver: a silver-white alloy containing copper and zinc and nickel


German silver: a silver-white alloy containing copper and zinc and nickel


nickel steel: an alloy steel containing nickel


nicotinamide adenine dinucleotide: a coenzyme present in most living cells and derived from the B vitamin nicotinic acid; serves as a reductant in various metabolic processes


NAD: a coenzyme present in most living cells and derived from the B vitamin nicotinic acid; serves as a reductant in various metabolic processes


nicotinamide adenine dinucleotide phosphate: a coenzyme similar to NAD and present in most living cells but serves as a reductant in different metabolic processes


NADP: a coenzyme similar to NAD and present in most living cells but serves as a reductant in different metabolic processes


Ni-hard: cast iron to which nickel has been added to make it resist abrasion


Ni-hard iron: cast iron to which nickel has been added to make it resist abrasion


Ni-resist: cast iron consisting of graphite in a matrix of austenite


Ni-resist iron: cast iron consisting of graphite in a matrix of austenite


nitride: a compound containing nitrogen and a more electropositive element (such as phosphorus or a metal)


nitrobenzene: a poisonous oily water-soluble liquid used as a solvent and in the manufacture of aniline


nitrofuran: derivative of furan used to inhibit bacterial growth


nitrogenase: an enzyme of nitrogen-fixing microorganisms that catalyzes the conversion of nitrogen to ammonia


nuclease: general term for enzymes that catalyze the hydrolysis of nucleic acid by cleaving chains of nucleotides into smaller units


nucleic acid: (biochemistry) any of various macromolecules composed of nucleotide chains that are vital constituents of all living cells


nucleoside: a glycoside formed by partial hydrolysis of a nucleic acid


nucleotide: a phosphoric ester of a nucleoside; the basic structural unit of nucleic acids (DNA or RNA)


base: a phosphoric ester of a nucleoside; the basic structural unit of nucleic acids (DNA or RNA)


nurse log: a large decomposing tree trunk that has fallen, usually in a forest; the decaying wood provides moisture and nutrients for a variety of insects and plants


cellulose acetate: an ester of acetic acid; used in fibers and fabrics; photographic films and varnishes


cellulose triacetate: cellulose acetate that is relatively slow to burn; used instead of celluloid for motion-picture film


triacetate: cellulose acetate that is relatively slow to burn; used instead of celluloid for motion-picture film


celluloid: highly flammable substance made from cellulose nitrate and camphor; used in e.g. motion-picture and X-ray film; its use has decreased with the development of nonflammable thermoplastics


cellulose xanthate: a cellulose ester obtained by treating cellulose with caustic soda


viscose: a cellulose ester obtained by treating cellulose with caustic soda


acrylic fiber: polymerized from acrylonitrile


acrylic: polymerized from acrylonitrile


polyamide: a polymer containing repeated amide groups


polymeric amide: a polymer containing repeated amide groups


nylon: a thermoplastic polyamide; a family of strong resilient synthetic fibers


oakum: loose hemp or jute fiber obtained by unravelling old ropes; when impregnated with tar it was used to caulk seams and pack joints in wooden ships


octane: any isomeric saturated hydrocarbon found in petroleum and used as a fuel and solvent


oil: a slippery or viscous liquid or liquefiable substance not miscible with water


fixed oil: nonvolatile animal or plant oil


fatty oil: nonvolatile animal or plant oil


fusel oil: a mixture of amyl alcohols and propanol and butanol formed from distillation of fermented liquors


gas oil: an oil formed through distillation of petroleum of intermediate boiling range and viscosity


stand oil: a thick oil comprised of linseed, tung, or soya oils which have been heated to over 300 C


neroli oil: an odoriferous yellow oil found in orange flowers and used in perfumery and as a flavoring


tall oil: an oil derived from wood pulp and used in making soaps or lubricants


oil-hardened steel: steel that is quenched in oil


oilpaper: paper that has been made translucent and waterproof by soaking in oil


oleic acid: a colorless oily liquid occurring as a glyceride; it is the major fatty acid in olive oil and canola oil; used in making soap and cosmetics and ointments and lubricating oils


oleo oil: obtained from beef fat; used in making margarine and soap and in lubrication


oleoresin capiscum: an oleoresin extracted from the capsicum pepper plant


oligosaccharide: any of the carbohydrates that yield only a few monosaccharide molecules on complete hydrolysis


onionskin: a thin strong lightweight translucent paper used especially for making carbon copies


flimsy: a thin strong lightweight translucent paper used especially for making carbon copies


india paper: a thin tough opaque paper used in fine books


onyx: a chalcedony with alternating black and white bands; used in making cameos


opaque gem: a gemstone that is opaque


opopanax: an odorous gum resin formerly used in medicines


organophosphate: an insecticide that interferes with an insect's nervous system


organophosphate nerve agent: any of a series of nerve agents containing organophosphate compounds first synthesized by German chemists in 1936; in World War II the Germans tested them in concentration camps but not on the battlefield; Iraq is alleged to have used them against Iran and against the Kurds


ormolu: brass that looks like gold; used to decorate furniture


oxalacetate: a salt or ester of oxalacetic acid


oxaloacetate: a salt or ester of oxalacetic acid


oxalacetic acid: an acid formed by oxidation of maleic acid (as in metabolism of fats and carbohydrates)


oxaloacetic acid: an acid formed by oxidation of maleic acid (as in metabolism of fats and carbohydrates)


oxalate: a salt or ester of oxalic acid


oxalic acid: a toxic colorless crystalline organic acid found in oxalis and other plants; used as a bleach and rust remover and in chemical analysis


ethanedioic acid: a toxic colorless crystalline organic acid found in oxalis and other plants; used as a bleach and rust remover and in chemical analysis


oxidase: any of the enzymes that catalyze biological oxidation


oxidation-reduction indicator: an indicator that shows a reversible color change between oxidized and reduced forms


oxide: any compound of oxygen with another element or a radical


oxidoreductase: an enzyme that catalyzes oxidation-reduction


oxime: any compound containing the group -C=NOH


oxyacetylene: a mixture of oxygen and acetylene; used to create high temperatures for cutting or welding metals


oxyacid: any acid that contains oxygen


oxygen acid: any acid that contains oxygen


periodic acid: any acid of iodine that contains oxygen


oxygenase: an oxidoreductase that catalyzes the incorporation of molecular oxygen


ozone: a colorless gas (O3) soluble in alkalis and cold water; a strong oxidizing agent; can be produced by electric discharge in oxygen or by the action of ultraviolet radiation on oxygen in the stratosphere (where it acts as a screen for ultraviolet radiation)


pad: a number of sheets of paper fastened together along one edge


pad of paper: a number of sheets of paper fastened together along one edge


tablet: a number of sheets of paper fastened together along one edge


palmitic acid: a saturated fatty acid that is the major fat in meat and dairy products


hexadecanoic acid: a saturated fatty acid that is the major fat in meat and dairy products


palmitin: an ester of glycerol and palmitic acid


pantothenic acid: a vitamin of the vitamin B complex that performs an important role in the oxidation of fats and carbohydrates and certain amino acids; occurs in many foods


pantothen: a vitamin of the vitamin B complex that performs an important role in the oxidation of fats and carbohydrates and certain amino acids; occurs in many foods


papain: a proteolytic enzyme obtained from the unripe papaya; used as a meat tenderizer


para aminobenzoic acid: a metabolic acid found in yeast and liver cells; used to make dyes and drugs and sun blockers


PABA: a metabolic acid found in yeast and liver cells; used to make dyes and drugs and sun blockers


paraquat: a poisonous yellow solid used in solution as a herbicide


paper: a material made of cellulose pulp derived mainly from wood or rags or certain grasses


paper tape: a long narrow strip of paper


paper toweling: absorbent paper used as toweling


papier-mache: a substance made from paper pulp that can be molded when wet and painted when dry


paper-mache: a substance made from paper pulp that can be molded when wet and painted when dry


papyrus: paper made from the papyrus plant by cutting it in strips and pressing it flat; used by ancient Egyptians and Greeks and Romans


parchment: a superior paper resembling sheepskin


rice paper: a thin delicate material resembling paper; made from the rice-paper tree


roofing paper: a heavy paper impregnated with tar and used as part of a roof for waterproofing


tar paper: a heavy paper impregnated with tar and used as part of a roof for waterproofing


ola: leaf or strip from a leaf of the talipot palm used in India for writing paper


olla: leaf or strip from a leaf of the talipot palm used in India for writing paper


ticker tape: a continuous thin ribbon of paper on which stock quotes are written


packing material: any material used especially to protect something


packing: any material used especially to protect something


wadding: any material used especially to protect something


excelsior: thin curly wood shavings used for packing or stuffing


wood shavings: thin curly wood shavings used for packing or stuffing


pantile: a roofing tile with a S-shape; laid so that curves overlap


blacktop: a black bituminous material used for paving roads or other areas; usually spread over crushed rock


blacktopping: a black bituminous material used for paving roads or other areas; usually spread over crushed rock


macadam: broken stone used in macadamized roadways


tarmacadam: a paving material of tar and broken stone; mixed in a factory and shaped during paving


tarmac: a paving material of tar and broken stone; mixed in a factory and shaped during paving


parget: plaster used to coat outer walls and line chimneys


pargeting: plaster used to coat outer walls and line chimneys


pargetting: plaster used to coat outer walls and line chimneys


paving: material used to pave an area


pavement: material used to pave an area


paving material: material used to pave an area


pay dirt: ore that yields a substantial profit to the miner


pearlite: a lamellar mixture of cementite and ferrite formed during the cooling of austenite; a constituent of steel and cast iron


pectic acid: a complex acid that occurs in ripe fruit and some vegetables


pectin: any of various water-soluble colloidal carbohydrates that occur in ripe fruit and vegetables; used in making fruit jellies and jams


pediculicide: a chemical agent that kills lice


penicillinase: enzyme produced by certain bacteria that inactivates penicillin and results in resistance to that antibiotic


beta-lactamase: enzyme produced by certain bacteria that inactivates penicillin and results in resistance to that antibiotic


pepsin: an enzyme produced in the stomach that splits proteins into peptones


pepsinogen: precursor of pepsin; stored in the stomach walls and converted to pepsin by hydrochloric acid in the stomach


perboric acid: a form of boric acid


perfluorocarbon: a powerful greenhouse gas emitted during the production of aluminum


PFC: a powerful greenhouse gas emitted during the production of aluminum


Permalloy: an 80/20 alloy of nickel and iron; easily magnetized and demagnetized


permanganate: a dark purple salt of permanganic acid; in water solution it is used as a disinfectant and antiseptic


permanganic acid: an unstable purple acid (HMnO4) known only in solution or of permanganate salts


peroxidase: any of a group of enzymes (occurring especially in plant cells) that catalyze the oxidation of a compound by a peroxide


peridot: a pale green variety of chrysolite; used as a gemstone


peroxide: an inorganic compound containing the divalent ion -O-O-


pesticide: a chemical used to kill pests (as rodents or insects)


petrochemical: any compound obtained from petroleum or natural gas


petroleum: a dark oil consisting mainly of hydrocarbons


crude oil: a dark oil consisting mainly of hydrocarbons


crude: a dark oil consisting mainly of hydrocarbons


rock oil: a dark oil consisting mainly of hydrocarbons


fossil oil: a dark oil consisting mainly of hydrocarbons


oil: a dark oil consisting mainly of hydrocarbons


residual oil: oil products that remain after petroleum has been distilled


resid: oil products that remain after petroleum has been distilled


petrolatum: a semisolid mixture of hydrocarbons obtained from petroleum; used in medicinal ointments and for lubrication


petroleum jelly: a semisolid mixture of hydrocarbons obtained from petroleum; used in medicinal ointments and for lubrication


mineral jelly: a semisolid mixture of hydrocarbons obtained from petroleum; used in medicinal ointments and for lubrication


system: (physical chemistry) a sample of matter in which substances in different phases are in equilibrium


phenolic plastic: a plastic consisting of phenolic resins


phenolic urea: a plastic consisting of phenolic resins


phenylalanine: an essential amino acid found in proteins and needed for growth of children and for protein metabolism in children and adults; abundant in milk and eggs; it is normally converted to tyrosine in the human body


phosgene: a colorless poisonous gas that smells like new-mown hay; used in chemical warfare


phosphatase: any of a group of enzymes that act as a catalyst in the hydrolysis of organic phosphates


phosphine: a colorless gas with a strong fishy smell; used as a pesticide


phosphate: a salt of phosphoric acid


orthophosphate: a salt of phosphoric acid


inorganic phosphate: a salt of phosphoric acid


phosphocreatine: an organic compound of creatine and phosphoric acid; found in the muscles of vertebrates where its hydrolysis releases energy for muscular contraction


creatine phosphate: an organic compound of creatine and phosphoric acid; found in the muscles of vertebrates where its hydrolysis releases energy for muscular contraction


creatine phosphoric acid: an organic compound of creatine and phosphoric acid; found in the muscles of vertebrates where its hydrolysis releases energy for muscular contraction


phospholipid: any of various compounds composed of fatty acids and phosphoric acid and a nitrogenous base; an important constituent of membranes


phosphoric acid: an acid used in fertilizers and soaps: H3PO4


orthophosphoric acid: an acid used in fertilizers and soaps: H3PO4


phthalic acid: a colorless acid used to make dyes and perfumes


phytochemical: a chemical substance obtained from plants that is biologically active but not nutritive


picric acid: a yellow toxic highly explosive strong acid; used in high explosives and as a dye and in chemical reactions


pig iron: crude iron tapped from a blast furnace


pig lead: lead that is cast in pigs


plasmin: an enzyme that dissolves the fibrin of blood clots


fibrinolysin: an enzyme that dissolves the fibrin of blood clots


plasminogen: an inactive form of plasmin that occurs in plasma and is converted to plasmin by organic solvents


plasminogen activator: protease produced in the kidney that converts plasminogen to plasmin and so initiates fibrinolysis


urokinase: protease produced in the kidney that converts plasminogen to plasmin and so initiates fibrinolysis


platinum black: a fine black powder of platinum; used as a catalyst in chemical reactions


polymerase: an enzyme that catalyzes the formation of new DNA and RNA from an existing strand of DNA or RNA


DNA polymerase: the enzyme responsible for DNA replication


transcriptase: the enzyme that copies DNA into RNA


RNA polymerase: the enzyme that copies DNA into RNA


reverse transcriptase: a polymerase that catalyzes the formation of DNA using RNA as a template; found especially in retroviruses


coloring material: any material used for its color


colouring material: any material used for its color


color: any material used for its color


colour: any material used for its color


dye: a usually soluble substance for staining or coloring e.g. fabrics or hair


dyestuff: a usually soluble substance for staining or coloring e.g. fabrics or hair


tincture: a substances that colors metals


argent: a metal tincture used in heraldry to give a silvery appearance


alizarin: an orange-red crystalline compound used in making red pigments and in dyeing


alizarine: an orange-red crystalline compound used in making red pigments and in dyeing


alizarin carmine: any of various acid dyes; used for dyeing wool scarlet red


alizarin crimson: any of various acid dyes; used for dyeing wool scarlet red


alizarin red: any of various acid dyes; used for dyeing wool scarlet red


bluing: used to whiten laundry or hair or give it a bluish tinge


blueing: used to whiten laundry or hair or give it a bluish tinge


blue: used to whiten laundry or hair or give it a bluish tinge


bromophenol blue: a dye used as an acid-base indicator


bromphenol blue: a dye used as an acid-base indicator


tetrabromo-phenolsulfonephthalein: a dye used as an acid-base indicator


bromothymol blue: a dye used as an acid-base indicator


bromthymol blue: a dye used as an acid-base indicator


cochineal: a red dyestuff consisting of dried bodies of female cochineal insects


cyanine dye: any of a class of dyes containing a -CH= group linking two heterocyclic rings containing nitrogen; used as sensitizers in photography


direct dye: dye with a high affinity for cellulose fibers (cotton or rayon etc.)


substantive dye: dye with a high affinity for cellulose fibers (cotton or rayon etc.)


eosin: a red fluorescent dye resulting from the action of bromine on fluorescein; used in cosmetics and as a biological stain for studying cell structures


bromeosin: a red fluorescent dye resulting from the action of bromine on fluorescein; used in cosmetics and as a biological stain for studying cell structures


fluorescein: a yellow dye that is visible even when highly diluted; used as an absorption indicator when silver nitrate solution is added to sodium chloride in order to precipitate silver chloride (turns pink when no chloride ions are left in solution and negative fluorescein ions are then absorbed)


fluoresceine: a yellow dye that is visible even when highly diluted; used as an absorption indicator when silver nitrate solution is added to sodium chloride in order to precipitate silver chloride (turns pink when no chloride ions are left in solution and negative fluorescein ions are then absorbed)


fluorescent dye: a yellow dye that is visible even when highly diluted; used as an absorption indicator when silver nitrate solution is added to sodium chloride in order to precipitate silver chloride (turns pink when no chloride ions are left in solution and negative fluorescein ions are then absorbed)


resorcinolphthalein: a yellow dye that is visible even when highly diluted; used as an absorption indicator when silver nitrate solution is added to sodium chloride in order to precipitate silver chloride (turns pink when no chloride ions are left in solution and negative fluorescein ions are then absorbed)


fluorescein isothiocyanate: a fluorochrome commonly conjugated with antibodies for use in indirect immunofluorescence


fluorescein isocyanate: a fluorochrome commonly conjugated with antibodies for use in indirect immunofluorescence


fluorochrome: any of various fluorescent substances used in fluorescence microscopy to stain specimens


hair dye: a dye or tint for the hair


hair coloring: a dye or tint for the hair


hematochrome: a reddish coloring material found in some algae


henna: a reddish brown dye used especially on hair


rinse: a liquid preparation used on wet hair to give it a tint


Kendal green: a green dye, often used to color cloth, which is obtained from the woad plant


Kendal: a green dye, often used to color cloth, which is obtained from the woad plant


lac dye: scarlet dye like cochineal; extracted with alkali from stick lac


lead acetate: a poisonous white solid (Pb[CH3CO]2) used in dyeing cotton and in making enamels and varnishes


sugar of lead: a poisonous white solid (Pb[CH3CO]2) used in dyeing cotton and in making enamels and varnishes


orchil: a purplish dye obtained from orchil lichens


archil: a purplish dye obtained from orchil lichens


cudbear: a purplish dye obtained from orchil lichens


phenol: any of a class of weakly acidic organic compounds; molecule contains one or more hydroxyl groups


pigment: dry coloring material (especially a powder to be mixed with a liquid to produce paint, etc.)


pigment: any substance whose presence in plant or animal tissues produces a characteristic color


bole: a soft oily clay used as a pigment (especially a reddish brown pigment)


lake: any of numerous bright translucent organic pigments


lake: a purplish red pigment prepared from lac or cochineal


orange: any pigment producing the orange color


watercolor: water-soluble pigment


water-color: water-soluble pigment


watercolour: water-soluble pigment


water-colour: water-soluble pigment


pine tar: a dark viscous substance obtained from the destructive distillation of pine wood


pisang wax: a wax obtained from the leaves of a plantain


plant material: material derived from plants


plant substance: material derived from plants


plant product: a product made from plant material


plasma: a green slightly translucent variety of chalcedony used as a gemstone


plaster: a mixture of lime or gypsum with sand and water; hardens into a smooth solid; used to cover walls and ceilings


plaster of Paris: any of several gypsum cements; a white powder (a form of calcium sulphate) that forms a paste when mixed with water and hardens into a solid; used in making molds and sculptures and casts for broken limbs


plaster: any of several gypsum cements; a white powder (a form of calcium sulphate) that forms a paste when mixed with water and hardens into a solid; used in making molds and sculptures and casts for broken limbs


puddle: a mixture of wet clay and sand that can be used to line a pond and that is impervious to water when dry


podzol: a soil that develops in temperate to cold moist climates under coniferous or heath vegetation; an organic mat over a grey leached layer


podzol soil: a soil that develops in temperate to cold moist climates under coniferous or heath vegetation; an organic mat over a grey leached layer


podsol: a soil that develops in temperate to cold moist climates under coniferous or heath vegetation; an organic mat over a grey leached layer


podsol soil: a soil that develops in temperate to cold moist climates under coniferous or heath vegetation; an organic mat over a grey leached layer


podsolic soil: a soil that develops in temperate to cold moist climates under coniferous or heath vegetation; an organic mat over a grey leached layer


poison gas: a gas that is poisonous to breath or contact; used in chemical warfare


polyester: a complex ester used for making fibers or resins or plastics or as a plasticizer


polyester: any of numerous synthetic resins; they are light and strong and weather resistant


polyester fiber: a quick-drying resilient synthetic fiber consisting primarily of polyester


polysaccharide: any of a class of carbohydrates whose molecules contain chains of monosaccharide molecules


polyose: any of a class of carbohydrates whose molecules contain chains of monosaccharide molecules


polymer: a naturally occurring or synthetic compound consisting of large molecules made up of a linked series of repeated simple monomers


polyphosphate: a salt or ester of polyphosphoric acid


polyunsaturated fat: a class of fats having long carbon chains with many double bonds unsaturated with hydrogen atoms; used in some margarines; supposedly associated with low blood cholesterol


potassium ferrocyanide: a cyanide compound that is prepared by the reaction of potassium cyanide with ferrous salts; commonly used by gardeners


yellow prussiate of potash: a cyanide compound that is prepared by the reaction of potassium cyanide with ferrous salts; commonly used by gardeners


potassium permanganate: a poisonous salt that forms dark purple crystals and is purple-red when dissolved in water; used as an oxidizing and bleaching agent and as a disinfectant and antiseptic


permanganate of potash: a poisonous salt that forms dark purple crystals and is purple-red when dissolved in water; used as an oxidizing and bleaching agent and as a disinfectant and antiseptic


sandstone: a sedimentary rock consisting of sand consolidated with some cement (clay or quartz etc.)


bluestone: bluish-grey sandstone used for paving and building


greensand: an olive-green sandstone containing glauconite


polish: a preparation used in polishing


polypropylene: a polymer of propylene used as a thermoplastic molding material


polypropene: a polymer of propylene used as a thermoplastic molding material


polyvinyl-formaldehyde: a polymer of vinyl formaldehyde


porphyry: any igneous rock with crystals embedded in a finer groundmass of minerals


porphyritic rock: any igneous rock with crystals embedded in a finer groundmass of minerals


porpoise oil: a yellow fatty oil obtained from porpoises and used as a fine lubricant


dolphin oil: an unsaturated fatty oil obtained from dolphins and used as a fine lubricant


potash: a potassium compound often used in agriculture and industry


caustic potash: a potassium compound often used in agriculture and industry


potassium hydroxide: a potassium compound often used in agriculture and industry


powder: a solid substance in the form of tiny loose particles; a solid that has been pulverized


pulverization: a solid substance in the form of tiny loose particles; a solid that has been pulverized


pulverisation: a solid substance in the form of tiny loose particles; a solid that has been pulverized


prairie soil: a type of soil occurring under grasses in temperate climates


precipitant: an agent that causes a precipitate to form


preservative: a chemical compound that is added to protect against decay or decomposition


product: a chemical substance formed as a result of a chemical reaction


percolate: the product of percolation


propanal: a colorless liquid aldehyde


propionaldehyde: a colorless liquid aldehyde


propanol: a clear colorless volatile liquid (alcohol) used as a solvent and antiseptic


propyl alcohol: a clear colorless volatile liquid (alcohol) used as a solvent and antiseptic


propenal: a pungent colorless unsaturated liquid aldehyde made from propene


acrolein: a pungent colorless unsaturated liquid aldehyde made from propene


propenoate: a salt or ester of propenoic acid


acrylate: a salt or ester of propenoic acid


propenoic acid: an unsaturated liquid carboxylic acid used in the manufacture of acrylic resins


acrylic acid: an unsaturated liquid carboxylic acid used in the manufacture of acrylic resins


propenonitrile: a colorless liquid unsaturated nitrile made from propene


acrylonitrile: a colorless liquid unsaturated nitrile made from propene


vinyl cyanide: a colorless liquid unsaturated nitrile made from propene


propylene: a flammable gas obtained by cracking petroleum; used in organic synthesis


propene: a flammable gas obtained by cracking petroleum; used in organic synthesis


propyl: the monovalent organic group C3H7- obtained from propane


propyl group: the monovalent organic group C3H7- obtained from propane


propyl radical: the monovalent organic group C3H7- obtained from propane


protease: any enzyme that catalyzes the splitting of proteins into smaller peptide fractions and amino acids by a process known as proteolysis


peptidase: any enzyme that catalyzes the splitting of proteins into smaller peptide fractions and amino acids by a process known as proteolysis


proteinase: any enzyme that catalyzes the splitting of proteins into smaller peptide fractions and amino acids by a process known as proteolysis


proteolytic enzyme: any enzyme that catalyzes the splitting of proteins into smaller peptide fractions and amino acids by a process known as proteolysis


ptomaine: any of various amines (such as putrescine or cadaverine) formed by the action of putrefactive bacteria


ptomain: any of various amines (such as putrescine or cadaverine) formed by the action of putrefactive bacteria


Pyrex: a borosilicate glass with a low coefficient of expansion; used for heat-resistant glassware in cooking and chemistry


pyrimidine: a heterocyclic organic compound with a penetrating odor


pyrimidine: any of several basic compounds derived from pyrimidine


pyrope: a deep red garnet used as a gemstone


pyrophoric alloy: an alloy that emits sparks when struck or scratched with steel; used in lighter flints


pyruvic acid: a colorless acid formed as an important intermediate in metabolism or fermentation


quassia: a bitter compound used as an insecticide and tonic and vermifuge; extracted from the wood and bark of trees of the genera Quassia and Picrasma


quenched steel: steel that has been hardened by immersing it in water or oil to cool it


quercitron: a yellow dye made from the bark of the quercitron oak tree


quinone: any of a class of aromatic yellow compounds including several that are biologically important as coenzymes or acceptors or vitamins; used in making dyes


benzoquinone: any of a class of aromatic yellow compounds including several that are biologically important as coenzymes or acceptors or vitamins; used in making dyes


radiopaque dye: dye that does not allow the passage of X rays or other radiation; used to outline certain organs during X-ray examination


rhodolite: a red or pink variety of garnet used as a gemstone


safranine: any of a class of chiefly red organic dyes


safranin: any of a class of chiefly red organic dyes


saffranine: any of a class of chiefly red organic dyes


pheno-safranine: a purplish red water-soluble dye used in microscopy


Tyrian purple: a red-purple to deep purple dye obtained from snails or made synthetically


vat dye: a water-insoluble dye that is applied by reducing the dye to an alkaline form, applying the dye, then regenerating the insoluble dye by oxidation in the material; used for dyeing cotton


vat color: a water-insoluble dye that is applied by reducing the dye to an alkaline form, applying the dye, then regenerating the insoluble dye by oxidation in the material; used for dyeing cotton


woad: a blue dyestuff obtained from the woad plant


radioactive material: material that is radioactive


radioactive waste: useless radioactive materials that are left after some laboratory or commercial process is completed


raffia: leaf fibers of the raffia palm tree; used to make baskets and mats etc.


raphia: leaf fibers of the raffia palm tree; used to make baskets and mats etc.


raffinose: a trisaccharide that occurs in sugar beets and cotton seeds and certain cereals


rauwolfia: any of several alkaloids extracted from the shrub Rauwolfia serpentina


raveling: a bit of fiber that has become separated from woven fabric


ravelling: a bit of fiber that has become separated from woven fabric


red brass: brass with enough copper to give it a reddish tint; used for plumbing pipe and other brass hardware and in cheap jewelry


guinea gold: brass with enough copper to give it a reddish tint; used for plumbing pipe and other brass hardware and in cheap jewelry


red lead: a reddish oxide of lead (Pb3O4) used as a pigment in paints and in glass and ceramics


minium: a reddish oxide of lead (Pb3O4) used as a pigment in paints and in glass and ceramics


red tide: seawater that is discolored by large numbers of certain dinoflagellates that produce saxitoxin


reductase: an enzyme that catalyses the biochemical reduction of some specified substance


refrigerant: any substance used to provide cooling (as in a refrigerator)


remover: a solvent that removes a substance (usually from a surface)


renin: a proteolytic enzyme secreted by the kidneys; catalyzes the formation of angiotensin and thus affects blood pressure


rennin: an enzyme that occurs in gastric juice; causes milk to coagulate


chymosin: an enzyme that occurs in gastric juice; causes milk to coagulate


residue: matter that remains after something has been removed


resorcinol: a crystalline phenol obtained from various resins; used in ointments for acne and in dandruff shampoos


restrainer: a chemical that is added to a photographic developer in order to retard development and reduce the amount of fog on a film


restriction endonuclease: any of the enzymes that cut nucleic acid at specific restriction sites and produce restriction fragments; obtained from bacteria (where they cripple viral invaders); used in recombinant DNA technology


restriction nuclease: any of the enzymes that cut nucleic acid at specific restriction sites and produce restriction fragments; obtained from bacteria (where they cripple viral invaders); used in recombinant DNA technology


restriction enzyme: any of the enzymes that cut nucleic acid at specific restriction sites and produce restriction fragments; obtained from bacteria (where they cripple viral invaders); used in recombinant DNA technology


retinene: either of two yellow to red retinal pigments formed from rhodopsin by the action of light


retinal: either of two yellow to red retinal pigments formed from rhodopsin by the action of light


ridge tile: a decorative tile that is bent in cross section; used to cover the ridge of a roof


roofing material: building material used in constructing roofs


rose quartz: a translucent rose-red variety of quartz used for ornaments


roughcast: a coarse plaster for the surface of external walls


latex: a milky exudate from certain plants that coagulates on exposure to air


rubber: an elastic material obtained from the latex sap of trees (especially trees of the genera Hevea and Ficus) that can be vulcanized and finished into a variety of products


natural rubber: an elastic material obtained from the latex sap of trees (especially trees of the genera Hevea and Ficus) that can be vulcanized and finished into a variety of products


India rubber: an elastic material obtained from the latex sap of trees (especially trees of the genera Hevea and Ficus) that can be vulcanized and finished into a variety of products


gum elastic: an elastic material obtained from the latex sap of trees (especially trees of the genera Hevea and Ficus) that can be vulcanized and finished into a variety of products


caoutchouc: an elastic material obtained from the latex sap of trees (especially trees of the genera Hevea and Ficus) that can be vulcanized and finished into a variety of products


crepe rubber: crude natural rubber; used mainly for shoe soles


rubber: any of various synthetic elastic materials whose properties resemble natural rubber


synthetic rubber: any of various synthetic elastic materials whose properties resemble natural rubber


silicone rubber: made from silicone elastomers; retains flexibility resilience and tensile strength over a wide temperature range


cold rubber: a rubber made at low temperatures (5 degrees Centigrade) which is tougher than conventional rubber and is often used in car tires


neoprene: a synthetic rubber that is resistant to oils and aging; used in waterproof products


hard rubber: a hard nonresilient rubber formed by vulcanizing natural rubber


vulcanite: a hard nonresilient rubber formed by vulcanizing natural rubber


ebonite: a hard nonresilient rubber formed by vulcanizing natural rubber


Para rubber: a type of natural rubber obtained from tropical South American trees


buna: made by polymerizing butadiene


buna rubber: made by polymerizing butadiene


butyl rubber: synthetic rubber made by polymerizing isobutylene


butyl: a hydrocarbon radical (C4H9)


ruby: a transparent deep red variety of corundum; used as a gemstone and in lasers


ruddle: a red iron ore used in dyeing and marking


reddle: a red iron ore used in dyeing and marking


raddle: a red iron ore used in dyeing and marking


rutile: a mineral consisting of titanium dioxide in crystalline form; occurs in metamorphic and plutonic rocks and is a major source of titanium


rain: drops of fresh water that fall as precipitation from clouds


rainwater: drops of fresh water that fall as precipitation from clouds


condensate: a product of condensation


seawater: water containing salts


saltwater: water containing salts


brine: water containing salts


evaporite: the sediment that is left after the evaporation of seawater


fresh water: water that is not salty


freshwater: water that is not salty


Rochelle salt: a double salt used in Seidlitz powder; acts as a cathartic


Rochelle salts: a double salt used in Seidlitz powder; acts as a cathartic


potassium sodium tartrate: a double salt used in Seidlitz powder; acts as a cathartic


Seidlitz powder: an effervescing salt containing sodium bicarbonate and Rochelle salt and tartaric acid; used as a cathartic


Seidlitz powders: an effervescing salt containing sodium bicarbonate and Rochelle salt and tartaric acid; used as a cathartic


Rochelle powder: an effervescing salt containing sodium bicarbonate and Rochelle salt and tartaric acid; used as a cathartic


salicylate: a salt of salicylic acid (included in several commonly used drugs)


salicylic acid: a white crystalline substance with a bitter aftertaste; used as a fungicide or in making aspirin or dyes or perfumes


2-hydroxybenzoic acid: a white crystalline substance with a bitter aftertaste; used as a fungicide or in making aspirin or dyes or perfumes


salmon oil: a fatty oil obtained from the wastes in canning salmon; used in making soap and dressing leather


salol: a white powder with a pleasant taste and odor; used to absorb light in sun tan lotions or as a preservative or an antiseptic or a coating for pills in which the medicine is intended for enteric release


phenyl salicylate: a white powder with a pleasant taste and odor; used to absorb light in sun tan lotions or as a preservative or an antiseptic or a coating for pills in which the medicine is intended for enteric release


salt: a compound formed by replacing hydrogen in an acid by a metal (or a radical that acts like a metal)


double salt: a solution of two simple salts that forms a single substance on crystallization


parathion: a colorless and odorless toxic oil used as an insecticide


Paris green: a toxic double salt of copper arsenate and copper acetate


rotenone: a white crystalline insecticide that has low toxicity for mammals; is used in home gardens; extracted from the roots of derris and cube


samarskite: a complex black mineral occurring in pegmatites


sapphirine: a rare light blue or green mineral; consists of aluminum and magnesium silicate and occurs as small grains in some metamorphic rocks


bile salt: a salt of bile acid and a base; functions as an emulsifier of lipids and fatty acids


Glauber's salt: (Na2SO4.10H2O) a colorless salt used as a cathartic


Glauber's salts: (Na2SO4.10H2O) a colorless salt used as a cathartic


cream of tartar: a salt used especially in baking powder


tartar: a salt used especially in baking powder


potassium bitartrate: a salt used especially in baking powder


potassium hydrogen tartrate: a salt used especially in baking powder


sodium chlorate: a colorless salt (NaClO3) used as a weed killer and an antiseptic


dichromic acid: the hypothetical acid (H2Cr2O7) from which dichromates are derived; known only in solution and in the form of dichromate salts


bichromate: a salt of the hypothetical dichromic acid


dichromate: a salt of the hypothetical dichromic acid


sodium dichromate: a red-orange salt used as a mordant


sodium bichromate: a red-orange salt used as a mordant


ammonium nitrate: used as an explosive and fertilizer and rocket propellant


silver nitrate: a nitrate used in making photographic emulsions; also used in medicine as a cautery and as a topical antibacterial agent


lunar caustic: silver nitrate fused into sticks and formerly used as a caustic


caustic: any chemical substance that burns or destroys living tissue


caulk: a waterproof filler and sealant that is used in building and repair to make watertight


caulking: a waterproof filler and sealant that is used in building and repair to make watertight


roan: a soft sheepskin leather that is colored and finished to resemble morocco; used in bookbinding


sodium hydroxide: a strongly alkaline caustic used in manufacturing soap and paper and aluminum and various sodium compounds


caustic soda: a strongly alkaline caustic used in manufacturing soap and paper and aluminum and various sodium compounds


silver bromide: a bromide that darkens when exposed to light; used in making photographic emulsions


silver iodide: an iodide that is used in photography, in seeding clouds to make rain, and in medicine


nitrate: any compound containing the nitrate group (such as a salt or ester of nitric acid)


nitro group: the group -NO3


nitrite: the radical -NO2 or any compound containing it (such as a salt or ester of nitrous acid)


sodium nitrite: nitrite used to preserve and color food especially in meat and fish products; implicated in the formation of suspected carcinogens


gunpowder: a mixture of potassium nitrate, charcoal, and sulfur in a 75:15:10 ratio which is used in gunnery, time fuses, and fireworks


powder: a mixture of potassium nitrate, charcoal, and sulfur in a 75:15:10 ratio which is used in gunnery, time fuses, and fireworks


smokeless powder: an explosive (trade name Ballistite) that burns with relatively little smoke; contains pyrocellulose and is used as a propellant


Ballistite: an explosive (trade name Ballistite) that burns with relatively little smoke; contains pyrocellulose and is used as a propellant


microcosmic salt: a white salt present in urine and used to test for metal oxides


chloride: any salt of hydrochloric acid (containing the chloride ion)


trichloride: any compound containing three chlorine atoms in each molecule


nitrogen trichloride: a yellow pungent volatile oil (trade name Agene) formerly used for bleaching and aging flour


Agene: a yellow pungent volatile oil (trade name Agene) formerly used for bleaching and aging flour


dichloride: a compound containing two chlorine atoms per molecule


bichloride: a compound containing two chlorine atoms per molecule


perchloride: a chloride containing an unusually high proportion of chlorine


chloride: any compound containing a chlorine atom


aluminum chloride: a chloride used as a wood preservative or catalyst


aluminium chloride: a chloride used as a wood preservative or catalyst


methylene chloride: a nonflammable liquid used as a solvent and paint remover and refrigerant


dichloromethane: a nonflammable liquid used as a solvent and paint remover and refrigerant


obidoxime chloride: a chloride used as an antidote for nerve gases such as sarin or VX


silver chloride: a chloride used chiefly in the manufacture of photographic emulsions


stannic chloride: a colorless caustic liquid made by treating tin with chlorine


stannous fluoride: a white powder that is used to fluoridate toothpaste


staple: a natural fiber (raw cotton, wool, hemp, flax) that can be twisted to form yarn


staple fiber: a natural fiber (raw cotton, wool, hemp, flax) that can be twisted to form yarn


staple fibre: a natural fiber (raw cotton, wool, hemp, flax) that can be twisted to form yarn


starch: a commercial preparation of starch that is used to stiffen textile fabrics in laundering


sand: a loose material consisting of grains of rock or coral


sangapenum: a variety of gum


gum sangapenum: a variety of gum


water sapphire: a deep blue cordierite often used as a gemstone


sapphire: a precious transparent stone of rich blue corundum valued as a gemstone


sarcosine: a sweetish crystalline amino acid


sard: a deep orange-red variety of chalcedony


sardine: a deep orange-red variety of chalcedony


sardius: a deep orange-red variety of chalcedony


sardine oil: oil obtained from sardines and used chiefly as a lubricant and in soap


sardonyx: an onyx characterized by parallel layers of sard and a different colored mineral


sawdust: fine particles of wood made by sawing wood


saw log: log large enough to be sawed into boards


saxitoxin: a powerful neurotoxin produced by certain dinoflagellates found in red tides; it can accumulate in mollusks that feed on the dinoflagellates and cause food poisoning to humans


scale wax: partly refined paraffin wax


paraffin scale: partly refined paraffin wax


scavenger: a chemical agent that is added to a chemical mixture to counteract the effects of impurities


scheelite: a mineral used as an ore of tungsten


schorl: black tourmaline


scrap iron: iron to be melted again and reworked


notepad: a pad of paper for keeping notes


scratch pad: pad for preliminary or hasty writing or notes or sketches etc;  is a British term


scratch paper: pad for preliminary or hasty writing or notes or sketches etc;  is a British term


scribbling block: pad for preliminary or hasty writing or notes or sketches etc;  is a British term


seal oil: a pale yellow to red-brown fatty oil obtained from seal blubber; used in making soap and dressing leather and as a lubricant


secretase: a set of enzymes believed to snip pieces off a longer protein producing fragments of amyloid protein that bunch up and create amyloid protein plaques in brain tissue (the pathological hallmark of Alzheimer's)


sedimentary clay: clay soil formed by sedimentary deposits


sepia: rich brown pigment prepared from the ink of cuttlefishes


serine: a sweetish crystalline amino acid involved in the synthesis by the body of cysteine


globulin: a family of proteins found in blood and milk and muscle and in plant seed


gamma globulin: a plasma protein containing the immunoglobulins that are responsible for immune responses


human gamma globulin: a plasma protein containing the immunoglobulins that are responsible for immune responses


myosin: the commonest protein in muscle; a globulin that combines with actin to form actomyosin


coagulation factor: any of the factors in the blood whose actions are essential for blood coagulation


clotting factor: any of the factors in the blood whose actions are essential for blood coagulation


fibrinogen: a protein present in blood plasma; converts to fibrin when blood clots


factor I: a protein present in blood plasma; converts to fibrin when blood clots


releasing factor: a substance produced by the hypothalamus that is capable of accelerating the secretion of a given hormone by the anterior pituitary gland


releasing hormone: a substance produced by the hypothalamus that is capable of accelerating the secretion of a given hormone by the anterior pituitary gland


RF: a substance produced by the hypothalamus that is capable of accelerating the secretion of a given hormone by the anterior pituitary gland


growth hormone-releasing factor: a releasing factor that accelerates the secretion of growth hormone by the anterior pituitary body


GHRF: a releasing factor that accelerates the secretion of growth hormone by the anterior pituitary body


intrinsic factor: a substance produced by the mucosa of the stomach and intestines that is essential for the absorption of vitamin B12


platelet: tiny bits of protoplasm found in vertebrate blood; essential for blood clotting


blood platelet: tiny bits of protoplasm found in vertebrate blood; essential for blood clotting


thrombocyte: tiny bits of protoplasm found in vertebrate blood; essential for blood clotting


porphyrin: any of various pigments distributed widely in living tissues


hemoglobin: a hemoprotein composed of globin and heme that gives red blood cells their characteristic color; function primarily to transport oxygen from the lungs to the body tissues


haemoglobin: a hemoprotein composed of globin and heme that gives red blood cells their characteristic color; function primarily to transport oxygen from the lungs to the body tissues


Hb: a hemoprotein composed of globin and heme that gives red blood cells their characteristic color; function primarily to transport oxygen from the lungs to the body tissues


myoglobin: a hemoprotein that receives oxygen from hemoglobin and stores it in the tissues until needed


oxyhemoglobin: the bright red hemoglobin that is a combination of hemoglobin and oxygen from the lungs


oxyhaemoglobin: the bright red hemoglobin that is a combination of hemoglobin and oxygen from the lungs


heme: a complex red organic pigment containing iron and other atoms to which oxygen binds


haem: a complex red organic pigment containing iron and other atoms to which oxygen binds


hematin: a complex red organic pigment containing iron and other atoms to which oxygen binds


haemitin: a complex red organic pigment containing iron and other atoms to which oxygen binds


protoheme: a complex red organic pigment containing iron and other atoms to which oxygen binds


hemin: a reddish-brown chloride of heme; produced from hemoglobin in laboratory tests for the presence of blood


protohemin: a reddish-brown chloride of heme; produced from hemoglobin in laboratory tests for the presence of blood


heterocyclic compound: a compound containing a heterocyclic ring


heterocyclic: a compound containing a heterocyclic ring


heterocycle: a compound containing a heterocyclic ring


cytochrome: (biochemistry) a class of hemoprotein whose principal biological function is electron transfer (especially in cellular respiration)


cytochrome c: the most abundant and stable cytochrome; involved in energy transfer


globin: a colorless protein obtained by removing heme from hemoglobin; the oxygen carrying compound in red blood cells


hematohiston: a colorless protein obtained by removing heme from hemoglobin; the oxygen carrying compound in red blood cells


haematohiston: a colorless protein obtained by removing heme from hemoglobin; the oxygen carrying compound in red blood cells


glutelin: a simple protein found in the seeds of cereals


histone: a simple protein containing mainly basic amino acids; present in cell nuclei in association with nucleic acids


prolamine: a simple protein found in plants


protamine: a simple protein found in fish sperm; rich in arginine; simpler in composition than globulin or albumin; counteracts the anticoagulant effect of heparin


scleroprotein: a simple protein found in horny and cartilaginous tissues and in the lens of the eye


albuminoid: a simple protein found in horny and cartilaginous tissues and in the lens of the eye


hemosiderin: a granular brown substance composed of ferric oxide; left from the breakdown of hemoglobin; can be a sign of disturbed iron metabolism


haemosiderin: a granular brown substance composed of ferric oxide; left from the breakdown of hemoglobin; can be a sign of disturbed iron metabolism


antibody: any of a large variety of proteins normally present in the body or produced in response to an antigen which it neutralizes, thus producing an immune response


autoantibody: an antibody acting against tissues of the organism that produces it


precipitin: an antibody that causes precipitation when it unites with its antigen


ABO antibodies: blood type antibodies


Rh antibody: rhesus factor antibody


antitoxin: an antibody that can neutralize a specific toxin


antivenin: an antitoxin that counteracts the effects of venom from the bite of a snake or insect or other animal


antivenene: an antitoxin that counteracts the effects of venom from the bite of a snake or insect or other animal


tetanus antitoxin: antitoxin given for short-term immunization against tetanus in cases of possible exposure to the tetanus bacillus


toxin antitoxin: a mixture of toxin and antitoxin used to immunize against a disease


agglutinin: an antibody that causes agglutination of a specific antigen


isoagglutinin: an antibody produced by one individual that causes agglutination of red blood cells in other individuals of the same species


agglutinogen: any substance that acts as an antigen to cause agglutinin production


isoagglutinogen: an antigen capable of causing the production of (or reacting with) an isoagglutinin


heterophil antibody: an antibody found in the blood of someone suffering from infectious mononucleosis


heterophile antibody: an antibody found in the blood of someone suffering from infectious mononucleosis


Forssman antibody: an antibody found in the blood of someone suffering from infectious mononucleosis


isoantibody: an antibody that occurs naturally against foreign tissues from a person of the same species


alloantibody: an antibody that occurs naturally against foreign tissues from a person of the same species


lysin: any substance (such as an antibody) or agent that can cause lysis


monoclonal antibody: any of a class of antibodies produced in the laboratory by a single clone of cells or a cell line and consisting of identical antibody molecules


monoclonal: any of a class of antibodies produced in the laboratory by a single clone of cells or a cell line and consisting of identical antibody molecules


infliximab: a monoclonal antibody (trade name Remicade) used to treat Crohn's disease and rheumatoid arthritis; administered by infusion; use and dosage must be determined by a physician


Remicade: a monoclonal antibody (trade name Remicade) used to treat Crohn's disease and rheumatoid arthritis; administered by infusion; use and dosage must be determined by a physician


opsonin: an antibody in blood serum that attaches to invading microorganisms and other antigens to make them more susceptible to the action of phagocytes


immunoglobulin: a class of proteins produced in lymph tissue in vertebrates and that function as antibodies in the immune response


Ig: a class of proteins produced in lymph tissue in vertebrates and that function as antibodies in the immune response


immune serum globulin: a class of proteins produced in lymph tissue in vertebrates and that function as antibodies in the immune response


immune gamma globulin: a class of proteins produced in lymph tissue in vertebrates and that function as antibodies in the immune response


immune globulin: a class of proteins produced in lymph tissue in vertebrates and that function as antibodies in the immune response


immunoglobulin A: one of the most common of the five major classes of immunoglobulins; the chief antibody in the membranes of the gastrointestinal and respiratory tracts


IgA: one of the most common of the five major classes of immunoglobulins; the chief antibody in the membranes of the gastrointestinal and respiratory tracts


immunoglobulin D: one of the five major classes of immunoglobulins; present in blood serum in small amounts


IgD: one of the five major classes of immunoglobulins; present in blood serum in small amounts


immunoglobulin E: one of the five major classes of immunoglobulins; present primarily in the skin and mucous membranes


IgE: one of the five major classes of immunoglobulins; present primarily in the skin and mucous membranes


reagin: an immunoglobulin E that is formed as an antibody against allergens (such as pollen); attaches to cell membranes causing the release of histamine and other substances responsible for the local inflammation characteristic of an allergy


immunoglobulin G: one of the five major classes of immunoglobulins; the main antibody defense against bacteria


IgG: one of the five major classes of immunoglobulins; the main antibody defense against bacteria


immunoglobulin M: one of the five major classes of immunoglobulins; involved in fighting blood infections and in triggering production of immunoglobulin G


IgM: one of the five major classes of immunoglobulins; involved in fighting blood infections and in triggering production of immunoglobulin G


tetanus immunoglobulin: sterile solution of globulins derived from the blood plasma of a person who has been immunized for tetanus; provides short-term immunization against tetanus in cases of possible exposure to the tetanus bacillus


tetanus immune globulin: sterile solution of globulins derived from the blood plasma of a person who has been immunized for tetanus; provides short-term immunization against tetanus in cases of possible exposure to the tetanus bacillus


poison: any substance that causes injury or illness or death of a living organism


toxicant: any substance that causes injury or illness or death of a living organism


poisonous substance: any substance that causes injury or illness or death of a living organism


chemical irritant: a substance producing irritation


capsaicin: colorless pungent crystalline compound derived from capsicum; source of the hotness of hot peppers of the genus Capsicum such as chili and cayenne and jalapeno


gingerol: derived from ginger; source of the hotness of ginger


piperin: derived from pepper (especially black pepper); source of the hotness of black and white pepper


piperine: derived from pepper (especially black pepper); source of the hotness of black and white pepper


isothiocyanate: a family of compounds derived from horseradish and radishes and onions and mustards; source of the hotness of those plants and preparations


fetoprotein: any of several antigens that occur naturally in the fetus and sometimes in adults with cancer


foetoprotein: any of several antigens that occur naturally in the fetus and sometimes in adults with cancer


alpha fetoprotein: an abnormally large amount of this fetoprotein in the fetus can signal an abnormality of the neural tube (as spina bifida or anencephaly)


alpha foetoprotein: an abnormally large amount of this fetoprotein in the fetus can signal an abnormality of the neural tube (as spina bifida or anencephaly)


AFP: an abnormally large amount of this fetoprotein in the fetus can signal an abnormality of the neural tube (as spina bifida or anencephaly)


toxin: a poisonous substance produced during the metabolism and growth of certain microorganisms and some higher plant and animal species


anatoxin: a bacterial toxin that has been weakened until it is no longer toxic but is strong enough to induce the formation of antibodies and immunity to the specific disease caused by the toxin


toxoid: a bacterial toxin that has been weakened until it is no longer toxic but is strong enough to induce the formation of antibodies and immunity to the specific disease caused by the toxin


animal toxin: a toxin resembling bacterial toxins in its antigenic properties that is found in the fluids of certain animals


zootoxin: a toxin resembling bacterial toxins in its antigenic properties that is found in the fluids of certain animals


bacterial toxin: any endotoxin or exotoxin formed in or elaborated by bacterial cells


botulin: potent bacterial toxin produced by the bacterium Clostridium botulinum that causes botulism; can be used as a bioweapon


botulinus toxin: potent bacterial toxin produced by the bacterium Clostridium botulinum that causes botulism; can be used as a bioweapon


botulismotoxin: potent bacterial toxin produced by the bacterium Clostridium botulinum that causes botulism; can be used as a bioweapon


cytotoxin: any substance that has a toxic effect on cells


endotoxin: a toxin that is confined inside the microorganisms and is released only when the microorganisms are broken down or die


enterotoxin: a cytotoxin specific for the cells of the intestinal mucosa


exotoxin: a toxin that is secreted by microorganisms into the surrounding medium


mephitis: a poisonous or foul smelling gas emitted from the earth


hepatotoxin: any toxin that affects the liver


nephrotoxin: any toxin that affects the kidneys


neurotoxin: any toxin that affects neural tissues


neurolysin: any toxin that affects neural tissues


mycotoxin: a toxin produced by a fungus


plant toxin: any substance produced by plants that is similar in its properties to extracellular bacterial toxin


phytotoxin: any substance produced by plants that is similar in its properties to extracellular bacterial toxin


venom: toxin secreted by animals; secreted by certain snakes and poisonous insects (e.g., spiders and scorpions)


kokoi venom: a potent neurotoxin found in a particular frog


snake venom: venom secreted by certain snakes


antigen: any substance (as a toxin or enzyme) that stimulates an immune response in the body (especially the production of antibodies)


antigenic determinant: the site on the surface of an antigen molecule to which an antibody attaches itself


determinant: the site on the surface of an antigen molecule to which an antibody attaches itself


epitope: the site on the surface of an antigen molecule to which an antibody attaches itself


rhesus factor: a blood group antigen possessed by Rh-positive people; if an Rh-negative person receives a blood transfusion from an Rh-positive person it can result in hemolysis and anemia


Rh factor: a blood group antigen possessed by Rh-positive people; if an Rh-negative person receives a blood transfusion from an Rh-positive person it can result in hemolysis and anemia


Rh: a blood group antigen possessed by Rh-positive people; if an Rh-negative person receives a blood transfusion from an Rh-positive person it can result in hemolysis and anemia


sap: a watery solution of sugars, salts, and minerals that circulates through the vascular system of a plant


scabicide: a drug that destroys the itch mite that causes scabies


sewer gas: foul-smelling gas that forms in sewers


shale: a sedimentary rock formed by the deposition of successive layers of clay


humic shale: shale that is rich in humic acids


oil shale: shale from which oil can be obtained by heating


shale oil: oil extracted from oil shale by heating


shark oil: a fatty yellow to brown oil obtained from the livers of sharks; used for dressing leather and as a source of vitamin A


shark-liver oil: a fatty yellow to brown oil obtained from the livers of sharks; used for dressing leather and as a source of vitamin A


sheep dip: a liquid mixture containing pesticides in which sheep are dipped to kill parasites


Shetland wool: a wool obtained from sheep of the Shetland islands


shingle: building material used as siding or roofing


shake: building material used as siding or roofing


shoe polish: a substance used to produce a shiny protective surface on footwear


blacking: a substance used to produce a shiny protective surface on footwear


shot metal: an alloy that is 98% lead and 2% arsenic; used in making small shot


siderite: iron ore in the form of ferrous carbonate


chalybite: iron ore in the form of ferrous carbonate


silicic acid: a jellylike substance (hydrated silica)


silicate: a salt or ester derived from silicic acid


silicide: any of various compounds of silicon with a more electropositive element or radical


silicon carbide: an extremely hard blue-black crystalline compound (SiC) used as an abrasive and a heat refractory material; crystals of silicon carbide can be used as semiconductors


silicone: any of a large class of siloxanes that are unusually stable over a wide range of temperatures; used in lubricants and adhesives and coatings and synthetic rubber and electrical insulation


silicone polymer: any of a large class of siloxanes that are unusually stable over a wide range of temperatures; used in lubricants and adhesives and coatings and synthetic rubber and electrical insulation


silicone resin: a polymeric silicone compound


siloxane: any of a large class of compounds that have alternate silicon and oxygen atoms


siding: material applied to the outside of a building to make it weatherproof


silex: a pure form of finely ground silica


silica: a white or colorless vitreous insoluble solid (SiO2); various forms occur widely in the earth's crust as quartz or cristobalite or tridymite or lechatelierite


silicon oxide: a white or colorless vitreous insoluble solid (SiO2); various forms occur widely in the earth's crust as quartz or cristobalite or tridymite or lechatelierite


silicon dioxide: a white or colorless vitreous insoluble solid (SiO2); various forms occur widely in the earth's crust as quartz or cristobalite or tridymite or lechatelierite


silica gel: a porous form of silica that is highly absorbent


silicon bronze: a bronze with 2-3% silicon that is resistant to corrosion


silk: animal fibers produced by silkworms and other larvae that spin cocoons and by most spiders


silt: mud or clay or small rocks deposited by a river or lake


siltstone: a fine-grained sandstone of consolidated silt


silvex: a herbicide that is effective in controlling woody plants but is toxic to animals


simazine: a herbicide used to control weeds (especially among crops)


Simoniz: a brand of car polish


sisal: a plant fiber used for making rope


sisal hemp: a plant fiber used for making rope


ski wax: wax used on the bottom of skis


slag: the scum formed by oxidation at the surface of molten metals


scoria: the scum formed by oxidation at the surface of molten metals


dross: the scum formed by oxidation at the surface of molten metals


slate: thin layers of rock used for roofing


slating: thin layers of rock used for roofing


smaltite: a grey mineral consisting of cobalt arsenide and nickel; an important source of cobalt and nickel


slush: partially melted snow


smelling salts: a pungent preparation of ammonium carbonate and perfume; sniffed as a stimulant to relieve faintness


snake oil: (medicine) any of various liquids sold as medicine (as by a travelling medicine show) but medically worthless


snow: a layer of snowflakes (white crystals of frozen water) covering the ground


snuff: the charred portion of a candlewick


corn snow: granular snow formed by alternate thawing and freezing


crud: heavy wet snow that is unsuitable for skiing


soapstone: a soft heavy compact variety of talc having a soapy feel; used to make hearths and tabletops and ornaments


soaprock: a soft heavy compact variety of talc having a soapy feel; used to make hearths and tabletops and ornaments


soap-rock: a soft heavy compact variety of talc having a soapy feel; used to make hearths and tabletops and ornaments


steatite: a soft heavy compact variety of talc having a soapy feel; used to make hearths and tabletops and ornaments


soda lime: a mixture of sodium and calcium hydroxides; absorbs liquids and gases


sodalite: a vitreous mineral consisting of sodium aluminum silicate and sodium chloride in crystalline form; occurs in igneous rocks


sodium carbonate: a sodium salt of carbonic acid; used in making soap powders and glass and paper


washing soda: a sodium salt of carbonic acid; used in making soap powders and glass and paper


sal soda: a sodium salt of carbonic acid; used in making soap powders and glass and paper


soda ash: a sodium salt of carbonic acid; used in making soap powders and glass and paper


soda: a sodium salt of carbonic acid; used in making soap powders and glass and paper


sodium carboxymethyl cellulose: a gummy substance that is a sodium salt of carboxymethyl cellulose; used as a thickening or emulsifying agent


sodium fluoride: a colorless crystalline salt of sodium (NaF) used in fluoridation of water and to prevent tooth decay


sodium hydride: a flammable grey crystalline binary compound (NaH)


sodium hypochlorite: an unstable salt (NaOCl) used as a bleaching agent and disinfectant


sodium iodide: a crystalline salt used like potassium iodide


sodium lauryl sulphate: a caustic detergent useful for removing grease; although commonly included in personal care items (shampoos and toothpastes etc.) it can irritate skin and should not be swallowed


sodium lauryl sulfate: a caustic detergent useful for removing grease; although commonly included in personal care items (shampoos and toothpastes etc.) it can irritate skin and should not be swallowed


SLS: a caustic detergent useful for removing grease; although commonly included in personal care items (shampoos and toothpastes etc.) it can irritate skin and should not be swallowed


sodium pyrophosphate: a sodium salt of pyrophosphoric acid used as a builder in soaps and detergents


tetrasodium pyrophosphate: a sodium salt of pyrophosphoric acid used as a builder in soaps and detergents


sodium sulphate: a solid white bitter salt used in manufacturing glass and paper and dyes and pharmaceuticals


sodium sulfate: a solid white bitter salt used in manufacturing glass and paper and dyes and pharmaceuticals


sodium tripolyphosphate: a sodium salt of triphosphoric acid used as a builder in soaps and detergents


sodium phosphate: phosphate of sodium; used as a laxative to cleanse the bowels


sodium orthophosphate: phosphate of sodium; used as a laxative to cleanse the bowels


soft water: water that is not hard (does not contain mineral salts that interfere with the formation of lather with soap)


solid: matter that is solid at room temperature and pressure


dry ice: solidified carbon dioxide; dry ice sublimates at -78.5 C and is used mainly as a refrigerant


solvent: a liquid substance capable of dissolving other substances


dissolvent: a liquid substance capable of dissolving other substances


dissolver: a liquid substance capable of dissolving other substances


dissolving agent: a liquid substance capable of dissolving other substances


resolvent: a liquid substance capable of dissolving other substances


solute: the dissolved matter in a solution; the component of a solution that changes its state


solvate: a compound formed by solvation (the combination of solvent molecules with molecules or ions of the solute)


solvating agent: an agent that converts something into a solvate


viricide: an agent (physical or chemical) that inactivates or destroys viruses


virucide: an agent (physical or chemical) that inactivates or destroys viruses


alkahest: hypothetical universal solvent once sought by alchemists


alcahest: hypothetical universal solvent once sought by alchemists


universal solvent: hypothetical universal solvent once sought by alchemists


soup: any composition having a consistency suggestive of soup


sourdough: a leaven of dough in which fermentation is active; used by pioneers for making bread


spackle: powder (containing gypsum plaster and glue) that when mixed with water forms a plastic paste used to fill cracks and holes in plaster


spackling compound: powder (containing gypsum plaster and glue) that when mixed with water forms a plastic paste used to fill cracks and holes in plaster


spar: any of various nonmetallic minerals (calcite or feldspar) that are light in color and transparent or translucent and cleavable


sparkle metal: matte that has 74 percent copper


spiegeleisen: pig iron containing manganese; used as a deoxidizing agent and to raise the manganese content in making steel


spiegel: pig iron containing manganese; used as a deoxidizing agent and to raise the manganese content in making steel


spiegel iron: pig iron containing manganese; used as a deoxidizing agent and to raise the manganese content in making steel


spill: liquid that is spilled


spelter: impure zinc containing about three percent lead and other impurities (especially in the form of ingots)


sperm oil: an animal oil found in the blubber of the sperm whale


spice: aromatic substances of vegetable origin used as a preservative


stacte: (Old Testament) one of several sweet-smelling spices used in incense


staff: building material consisting of plaster and hair; used to cover external surfaces of temporary structure (as at an exposition) or for decoration


staphylococcal enterotoxin: a soluble exotoxin produced by some strains of staphylococcus; a cause of food poisoning


staphylococcal enterotoxin B: a form of staphylococcal enterotoxin that has been used as an incapacitating agent in biological warfare


SEB: a form of staphylococcal enterotoxin that has been used as an incapacitating agent in biological warfare


spinel: a hard glassy mineral consisting of an oxide of magnesium and aluminum; occurs in various colors that are used as gemstones


spinel ruby: a spinel used as a gemstone (usually dark red)


ruby spinel: a spinel used as a gemstone (usually dark red)


almandine: a purple variety of the ruby spinel


balas: a pale rose-colored variety of the ruby spinel


balas ruby: a pale rose-colored variety of the ruby spinel


Ceylonite: a dark-colored spinel containing iron


pleonaste: a dark-colored spinel containing iron


rubicelle: a yellow or orange variety of ruby spinel


solid solution: a homogeneous solid that can exist over a range of component chemicals; a constituent of alloys that is formed when atoms of an element are incorporated into the crystals of a metal


primary solid solution: a homogeneous solid that can exist over a range of component chemicals; a constituent of alloys that is formed when atoms of an element are incorporated into the crystals of a metal


spirits of ammonia: a solution of ammonium carbonate in ammonia water and alcohol


sal volatile: a solution of ammonium carbonate in ammonia water and alcohol


spodumene: a pyroxene mineral consisting of lithium aluminum silicate; a source of lithium


hiddenite: a green transparent form of the mineral spodumene used as a gemstone


spray: a pesticide in suspension or solution; intended for spraying


stabilizer: a chemical that is added to a solution or mixture or suspension to maintain it in a stable or unchanging state


stachyose: a tetrasaccharide found in the tubers of the Chinese artichoke


stain: (microscopy) a dye or other coloring material that is used in microscopy to make structures visible


counterstain: a stain of contrasting color that is used when the principal stain does not show the structure clearly


Gram's solution: a solution used in staining bacteria by Gram's method; consists of one part iodine and two parts potassium iodide and 300 parts water


stannite: a dark grey mineral with a metallic luster that is a source of tin


tin pyrites: a dark grey mineral with a metallic luster that is a source of tin


star sapphire: a sapphire that when cut shows a starlike figure in reflected light because of its crystalline structure


starch: a complex carbohydrate found chiefly in seeds, fruits, tubers, roots and stem pith of plants, notably in corn, potatoes, wheat, and rice; an important foodstuff and used otherwise especially in adhesives and as fillers and stiffeners for paper and textiles


amylum: a complex carbohydrate found chiefly in seeds, fruits, tubers, roots and stem pith of plants, notably in corn, potatoes, wheat, and rice; an important foodstuff and used otherwise especially in adhesives and as fillers and stiffeners for paper and textiles


arrowroot: a nutritive starch obtained from the root of the arrowroot plant


cornstarch: starch prepared from the grains of corn; used in cooking as a thickener


cornflour: starch prepared from the grains of corn; used in cooking as a thickener


sago: powdery starch from certain sago palms; used in Asia as a food thickener and textile stiffener


pearl sago: sago ground into small round grains


amyloid: a non-nitrogenous food substance consisting chiefly of starch; any substance resembling starch


Otaheite arrowroot: a starch obtained from the root of the pia


Otaheite arrowroot starch: a starch obtained from the root of the pia


steam: water at boiling temperature diffused in the atmosphere


live steam: steam coming from a boiler at full pressure


water vapor: water in a vaporous form diffused in the atmosphere but below boiling temperature


water vapour: water in a vaporous form diffused in the atmosphere but below boiling temperature


vapor: a visible suspension in the air of particles of some substance


vapour: a visible suspension in the air of particles of some substance


softener: a substance added to another to make it less hard


water softener: a substance (such as sodium chloride) that lessens the hardness of water by replacing calcium and magnesium ions with sodium ions and so gives the water more efficient sudsing power


soman: a nerve agent easily absorbed into the body; a lethal cholinesterase inhibitor that is highly toxic when inhaled


GD: a nerve agent easily absorbed into the body; a lethal cholinesterase inhibitor that is highly toxic when inhaled


spray: water in small drops in the atmosphere; blown from waves or thrown up by a waterfall


sea spray: spray from ocean waves


spindrift: spray blown up from the surface of the sea


spoondrift: spray blown up from the surface of the sea


stearic acid: a waxy saturated fatty acid; occurs widely as a glyceride in animal and vegetable fats


octadecanoic acid: a waxy saturated fatty acid; occurs widely as a glyceride in animal and vegetable fats


stearin: an ester of glycerol and stearic acid


Stellite: a very hard alloy of cobalt and chromium with cobalt as the principal ingredient; used to make cutting tools and for surfaces subject to heavy wear


sterling silver: a silver alloy with no more than 7.5% copper


sternutator: a chemical substance that causes sneezing and coughing and crying


sternutatory: a chemical substance that causes sneezing and coughing and crying


steroid: any of several fat-soluble organic compounds having as a basis 17 carbon atoms in four rings; many have important physiological effects


nonsteroid: an organic compound that does no contain a steroid


nonsteroidal: an organic compound that does no contain a steroid


ketosteroid: a steroid containing a ketone group


sterol: any of a group of natural steroid alcohols derived from plants or animals; they are waxy insoluble substances


steroid alcohol: any of a group of natural steroid alcohols derived from plants or animals; they are waxy insoluble substances


cholesterol: an animal sterol that is normally synthesized by the liver; the most abundant steroid in animal tissues


cholesterin: an animal sterol that is normally synthesized by the liver; the most abundant steroid in animal tissues


HDL cholesterol: the cholesterol in high-density lipoproteins; the `good' cholesterol; a high level in the blood is thought to lower the risk of coronary artery disease


LDL cholesterol: the cholesterol in low-density lipoproteins; the `bad' cholesterol; a high level in the blood is thought to be related to various pathogenic conditions


oxidized LDL cholesterol: LDL cholesterol that has been bombarded by free radicals; it is thought to cause atherosclerosis


ergosterol: a plant sterol that is converted into vitamin D by ultraviolet radiation


bile acid: any of the steroid acids generated in the liver and stored with bile


cholic acid: an insoluble crystalline acid present in bile


bilge: water accumulated in the bilge of a ship


bilge water: water accumulated in the bilge of a ship


cardiac glycoside: obtained from a number of plants and used to stimulate the heart in cases of heart failure


cardiac glucoside: obtained from a number of plants and used to stimulate the heart in cases of heart failure


digitalis: a powerful cardiac stimulant obtained from foxglove


digitalis glycoside: a powerful cardiac stimulant obtained from foxglove


digitalin: a powerful cardiac stimulant obtained from foxglove


render: a substance similar to stucco but exclusively applied to masonry walls


stibnite: a soft grey mineral; the chief ore of antimony


sticks and stone: a general term for building materials


wattle and daub: building material consisting of interwoven rods and twigs covered with clay


stiffener: material used for stiffening something


streptodornase: an enzyme produced by some hemolytic strains of streptococcus that dissolves fibrinous secretions from infections; used medicinally (often in combination with streptokinase)


streptokinase: an enzyme produced by some strains of streptococcus that can liquefy blood clots by converting plasminogen to plasmin; used medicinally in some cases of myocardial infarction and pulmonary embolism


streptolysin: any of several hemolysins derived from strains of streptococcus


stripper: a chemical compound used to remove paint or varnish


strophanthin: a bitter and very toxic glycoside derived from plants of the genus Strophanthus; in moderate doses it is a cardiac stimulant but in larger doses it is a powerful poison; used in Africa as an arrow poison


strontianite: a mineral consisting of strontium carbonate


stucco: a plaster now made mostly from Portland cement and sand and lime; applied while soft to cover exterior walls or surfaces


sublimate: the product of vaporization of a solid


tallow: obtained from suet and used in making soap, candles and lubricants


vegetable tallow: a waxy fat obtained from certain plants (e.g. bayberry) and used as tallow


sucrose: a complex carbohydrate found in many plants and used as a sweetening agent


saccharose: a complex carbohydrate found in many plants and used as a sweetening agent


jaggery: unrefined brown sugar made from palm sap


jagghery: unrefined brown sugar made from palm sap


jaggary: unrefined brown sugar made from palm sap


structural iron: iron that has been cast or worked in structural shapes


structural steel: a strong steel that is rolled into shapes that are used in construction


sulfanilic acid: a crystalline acid made from aniline and used as a dye


sulphanilic acid: a crystalline acid made from aniline and used as a dye


sulfate: a salt or ester of sulphuric acid


sulphate: a salt or ester of sulphuric acid


sulfide: a compound of sulphur and some other element that is more electropositive


sulphide: a compound of sulphur and some other element that is more electropositive


sulfur oxide: any of several oxides of sulphur


sulphur oxide: any of several oxides of sulphur


sulfur dioxide: a colorless toxic gas (SO2) that occurs in the gases from volcanoes; used in many manufacturing processes and present in industrial emissions; causes acid rain


sulphur dioxide: a colorless toxic gas (SO2) that occurs in the gases from volcanoes; used in many manufacturing processes and present in industrial emissions; causes acid rain


sulfur hexafluoride: a colorless gas that is soluble in alcohol and ether; a powerful greenhouse gas widely used in the electrical utility industry


sulphur hexafluoride: a colorless gas that is soluble in alcohol and ether; a powerful greenhouse gas widely used in the electrical utility industry


sunstone: a translucent quartz spangled with bits of mica or other minerals


aventurine: a translucent quartz spangled with bits of mica or other minerals


superoxide: the univalent anion O2-


superoxide anion: the univalent anion O2-


superoxide: a metallic oxide containing the univalent anion O2-


superoxide dismutase: an enzyme that catalyzes the conversion of superoxide into hydrogen peroxide and oxygen


SOD: an enzyme that catalyzes the conversion of superoxide into hydrogen peroxide and oxygen


surgical spirit: methylated spirit used in the practice of medicine (especially for cleansing the skin before injections or before surgery)


Swedish iron: wrought iron of high purity made in Sweden


swinging chad: a chad that is incompletely removed and still attached at two corners


sylvanite: a silver-white mineral consisting of silver gold telluride; a source of gold in Australia and America


graphic tellurium: a silver-white mineral consisting of silver gold telluride; a source of gold in Australia and America


sylvite: a mineral consisting of native potassium chloride; an important ore of potassium that is found in sedimentary beds


sylvine: a mineral consisting of native potassium chloride; an important ore of potassium that is found in sedimentary beds


tabun: the first known nerve agent, synthesized by German chemists in 1936; a highly toxic combustible liquid that is soluble in organic solvents and is used as a nerve gas in chemical warfare


GA: the first known nerve agent, synthesized by German chemists in 1936; a highly toxic combustible liquid that is soluble in organic solvents and is used as a nerve gas in chemical warfare


talc: a fine grained mineral having a soft soapy feel and consisting of hydrated magnesium silicate; used in a variety of products including talcum powder


talcum: a fine grained mineral having a soft soapy feel and consisting of hydrated magnesium silicate; used in a variety of products including talcum powder


French chalk: a soft white compact talc used to mark cloth or to remove grease stains


rensselaerite: a kind of soft talc; sometimes used as wood filler


tallow oil: an animal oil obtained by pressing tallow; used as a lubricant


tannin: any of various complex phenolic substances of plant origin; used in tanning and in medicine


tannic acid: any of various complex phenolic substances of plant origin; used in tanning and in medicine


catechin: a tannic acid that is extracted from black catechu as a white crystalline substance


tantalite: a mineral consisting of tantalum oxide of iron and manganese that occurs with niobite or in coarse granite; an ore of tantalum


tartaric acid: an acid found in many fruits; used in soft drinks and confectionery and baking powder


racemic acid: the optically inactive form of tartaric acid that is often found in grape juice


tear gas: a gas that makes the eyes fill with tears but does not damage them; used in dispersing crowds


teargas: a gas that makes the eyes fill with tears but does not damage them; used in dispersing crowds


lacrimator: a gas that makes the eyes fill with tears but does not damage them; used in dispersing crowds


lachrymator: a gas that makes the eyes fill with tears but does not damage them; used in dispersing crowds


telluride: any binary compound of tellurium with other more electropositive elements


telomerase: an enzyme in eukaryotic cells that can add telomeres to the ends of chromosomes after they divide


tenderizer: a substance (as the plant enzyme papain) applied to meat to make it tender


tenderiser: a substance (as the plant enzyme papain) applied to meat to make it tender


terpene: an unsaturated hydrocarbon obtained from plants


tetrachloride: any compound that contains four chlorine atoms per molecule


tetrafluoroethylene: a flammable gaseous fluorocarbon used in making plastics (polytetrafluoroethylene resins)


tetrahalide: any halide containing four halogen atoms in its molecules


tetrasaccharide: any of a variety of carbohydrates that yield four monosaccharide molecules on complete hydrolysis


tetrodotoxin: a powerful neurotoxin found in the ovaries of pufferfish


tetroxide: an oxide containing four atoms of oxygen in the molecule


tetryl: a yellow crystalline explosive solid that is used in detonators


nitramine: a yellow crystalline explosive solid that is used in detonators


thatch: plant stalks used as roofing material


thickening: any material used to thicken


thickener: any material used to thicken


thiouracil: depresses the function of the thyroid gland


thiocyanate: a salt of thiocyanic acid; formed when alkaline cyanides are fused with sulfur


thiocyanic acid: an unstable acid that can be obtained by distilling a thiocyanate salt


thorite: a radioactive mineral consisting of thorium silicate; it is a source of thorium that is found in coarse granite


thortveitite: a mineral consisting of scandium yttrium silicate; a source of scandium


threonine: a colorless crystalline amino acid found in protein; occurs in the hydrolysates of certain proteins; an essential component of human nutrition


prothrombin: a protein in blood plasma that is the inactive precursor of thrombin


factor II: a protein in blood plasma that is the inactive precursor of thrombin


thromboplastin: an enzyme liberated from blood platelets that converts prothrombin into thrombin as blood starts to clot


thrombokinase: an enzyme liberated from blood platelets that converts prothrombin into thrombin as blood starts to clot


factor III: an enzyme liberated from blood platelets that converts prothrombin into thrombin as blood starts to clot


calcium ion: ion of calcium; a factor in the clotting of blood


factor IV: ion of calcium; a factor in the clotting of blood


proaccelerin: a coagulation factor


prothrombin accelerator: a coagulation factor


accelerator factor: a coagulation factor


factor V: a coagulation factor


proconvertin: a coagulation factor formed in the kidney under the influence of vitamin K


cothromboplastin: a coagulation factor formed in the kidney under the influence of vitamin K


stable factor: a coagulation factor formed in the kidney under the influence of vitamin K


factor VII: a coagulation factor formed in the kidney under the influence of vitamin K


antihemophilic factor: a coagulation factor (trade name Hemofil) whose absence is associated with hemophilia A


antihaemophilic factor: a coagulation factor (trade name Hemofil) whose absence is associated with hemophilia A


antihemophilic globulin: a coagulation factor (trade name Hemofil) whose absence is associated with hemophilia A


antihaemophilic globulin: a coagulation factor (trade name Hemofil) whose absence is associated with hemophilia A


factor VIII: a coagulation factor (trade name Hemofil) whose absence is associated with hemophilia A


Hemofil: a coagulation factor (trade name Hemofil) whose absence is associated with hemophilia A


Christmas factor: coagulation factor whose absence is associated with hemophilia B


factor IX: coagulation factor whose absence is associated with hemophilia B


prothrombinase: coagulation factor that is converted to an enzyme that converts prothrombin to thrombin in a reaction that depends on calcium ions and other coagulation factors


factor X: coagulation factor that is converted to an enzyme that converts prothrombin to thrombin in a reaction that depends on calcium ions and other coagulation factors


plasma thromboplastin antecedent: coagulation factor whose deficiency results in a hemorrhagic tendency


factor XI: coagulation factor whose deficiency results in a hemorrhagic tendency


Hageman factor: coagulation factor whose deficiency results in prolongation of clotting time of venous blood


factor XII: coagulation factor whose deficiency results in prolongation of clotting time of venous blood


fibrinase: in the clotting of blood thrombin catalyzes factor XIII into its active form (fibrinase) which causes fibrin to form a stable clot


factor XIII: in the clotting of blood thrombin catalyzes factor XIII into its active form (fibrinase) which causes fibrin to form a stable clot


thymine: a base found in DNA (but not in RNA) and derived from pyrimidine; pairs with adenine


T: a base found in DNA (but not in RNA) and derived from pyrimidine; pairs with adenine


deoxyadenosine: a nucleoside component of DNA; composed of adenosine and deoxyribose


deoxycytidine: a nucleoside component of DNA; composed of cytosine and deoxyribose


cytidine: a nucleoside component of DNA; composed of cytosine and deoxyribose


deoxyguanosine: a nucleoside component of DNA; composed of guanine and deoxyribose


guanosine: a nucleoside component of DNA; composed of guanine and deoxyribose


deoxythymidine: a nucleoside component of DNA; composed of thymine and deoxyribose


thymidine: a nucleoside component of DNA; composed of thymine and deoxyribose


thymol: a colorless crystalline solid used in perfume or preserving biological specimens or in embalming or medically as a fungicide or antiseptic


thyme camphor: a colorless crystalline solid used in perfume or preserving biological specimens or in embalming or medically as a fungicide or antiseptic


thymic acid: a colorless crystalline solid used in perfume or preserving biological specimens or in embalming or medically as a fungicide or antiseptic


melanocyte-stimulating hormone: a hormone secreted by the anterior pituitary gland that controls the degree of pigmentation in melanocytes


MSH: a hormone secreted by the anterior pituitary gland that controls the degree of pigmentation in melanocytes


thyrotropin: anterior pituitary hormone that stimulates the function of the thyroid gland


thyrotropic hormone: anterior pituitary hormone that stimulates the function of the thyroid gland


thyrotrophin: anterior pituitary hormone that stimulates the function of the thyroid gland