Definitions for "Operculum"
Keywords:  gill, lid, bony, opercula, gastropod
The lid of a pitcherform leaf.
The lid of the urnlike capsule of mosses.
Any lidlike or operculiform process or part; as, the opercula of a dental follicle.
The operculum is a smooth and featherless patch of skin located where the beak attaches to the forehead of certain birds. It is often enlarged and brightly colored such as one can observe in pigeons, parrots and birds of prey. It is also called the cere.
fleshy partial covering over nostril
Swollen structure in pigeons overarching the nostril.
in eucalypts, the cap (or caps) of a flower bud which is formed by the fusion of the sepals or the petals, and dehisces at maturity exposing the reproductive organs
in a flower, a cap formed by fusion or cohesion of perianth parts and covering the stamens and carpels in the bud, becoming detached at maturity by abscission; especially in Eucalyptus, see calyptra.