n.
Pronunciation: ō - ' p ə r-ky ə -l ə m
Function: noun
Inflected Form: plural -la \ -l ə \ also -lums
Etymology: New Latin, from Latin, cover, from operire to shut, cover
Date: 1681
1 : a body process or part that suggests a lid: as a : a horny or shelly plate on the posterior dorsal surface of the foot in many gastropod mollusks that closes the shell when the animal is retracted b : the covering of the gills of a fish ― see FISH illustration
2 : a lid or covering flap (as of a moss capsule)