noun, plural o·per·cu·la [oh-pur-kyuh-luh] /oʊˈpɜr kyə lə/, o·per·cu·lums.
- the gill cover of fishes and amphibians.
- (in many gastropods) a horny plate that closes the opening of the shell when the animal is retracted.
Origin of operculum
Examples from the Web for opercular
Historical Examples of opercular
The Opercular Valves are large, owing to the form of the shell.
The al are added to above the level of the opercular membrane.
They are joined to the sheath of the shell by the opercular membrane.
The opercular has a facet for articulation with the hyomandibular.The Vertebrate Skeleton
Sidney H. Reynolds
The opercular valves, or pieces placed so as to enclose the aperture.A Conchological Manual
George Brettingham Sowerby
noun plural -la (-lə) or -lums
- the hard bony flap covering the gill slits in fishes
- the bony plate in certain gastropods covering the opening of the shell when the body is withdrawn
Word Origin for operculum
1713, from Latin operculum "cover, lid," from operire "to cover, close" (see weir), with instrumental suffix *-tlom. Related: Opercular.