As nouns the difference between operculum and opercular
is that operculum is a covering flap or lidlike structure in plants and animals, such as a gill cover while opercular is (anatomy) the principal opercular bone or operculum of fishes.
As an adjective opercular is
of or pertaining to the operculum.
operculum
English
Noun
(opercula)
A covering flap or lidlike structure in plants and animals, such as a gill cover
opercular
English
Adjective
(-)
Of or pertaining to the operculum.