A popliteal cyst, also known as a Baker's cyst, is a fluid-filled swelling that causes a lump at the back of the knee.
the smallest category is species but from largest to smallest it will be: kingdom Phylum class order family genus and species and you can come up with another word for it to hâ¦elp you with it. so yeh there you go.
Tweet. 1  The smallest animal in the world, which is also the smallest insect in the world (so far) is the Megaphragma caribea otherwise known as a fairyfly. It is a parasitic wasp that lives on the island of Guadalope and feeds off the eggs of other insects. Specimens have been found between 0.10 mm to 0.17 mm in length.