See more synonyms on Thesaurus.com. noun, (used with a singular verb) 1. Biology. the science of heredity, dealing with resemblances and differences of related organisms resulting from the interaction of their genes and the environment.
Rx: A medical prescription. The symbol Rx is usually said to stand for the Latin word recipe meaning to take.. It is customarily part of the superscription (heading) of a prescription.
Different jurisdictions have different definitions of what constitutes a prescription drug. Rx is often used as a short form for prescription drug in North America-a contraction of the Latin word  recipe  (an imperative form of recipere) meaning take.