Main Entry:

oper·cu·lum

Pronunciation:

\ō-ˈpər-kyə-ləm\

Function:

noun

Inflected Form(s):

plural oper·cu·la \-lə\ also oper·cu·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)