lar·va 
(lärvə)
(lärvə)n. pl. lar·vae (-vē) or lar·vas
1.
a. The newly hatched, wingless, often wormlike form of many insects, developing into a pupa in species that undergo complete metamorphosis.
b. The six-legged immature form of a tick or mite.
2. The newly hatched, earliest form of any of various animals that undergo metamorphosis, differing markedly in appearance from the adult.
3. Roman Mythology A malevolent spirit of the dead.
[Latin lārva, specter, mask (because it acts as a specter of or a mask for the adult form).]
larval adj.
Word History: The word larva referring to the newly hatched form of insects before they undergo metamorphosis comes from the Latin word lārva, meaning "evil spirit, ghost, demon." The Latin word also was used to mean "a terrifying mask," such as one that might have been worn by a Roman performer in the role of such an evil spirit. In the 1600s and 1700s, scientists began to use the Latin word to describe the stage in an insect's life during which its final form is still hidden—the larval stage is a mask, so to speak, that the insect will later remove to reveal its adult appearance.