Definition of operculum
plural oper·cu·laplay \-lə\ also oper·cu·lums
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)
Origin of operculum
New Latin, from Latin, cover, from operire to shut, cover
First Known Use: 1681
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Medical Dictionary: Definition of "operculum"
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