operculum

[ oh-pur-kyuh-luhm ]

noun

, plural o·per·cu·la [oh-, pur, -ky, uh, -l, uh], o·per·cu·lums.

1. Botany, Zoology. a part or organ serving as a lid or cover, as a covering flap on a seed vessel.
2. Zoology.
   1. the gill cover of fishes and amphibians.
   2. (in many gastropods) a horny plate that closes the opening of the shell when the animal is retracted.

operculum

/ əʊˈpɜːkjʊləm; əʊˈpɜːkjʊlɪt; -ˌleɪt /

noun

1. zoology
   1. the hard bony flap covering the gill slits in fishes
   2. the bony plate in certain gastropods covering the opening of the shell when the body is withdrawn
2. botany the covering of the spore-bearing capsule of a moss
3. biology any other covering or lid in various organisms

operculum

/ ō-pûr′kyə-ləm /

, Plural opercula

1. A lid or flap covering an opening, such as the gill cover in some fish or the horny flap covering the opening of a snail.

Derived Forms

• oˈpercular, adjective

Other Words From

• o·percu·lar adjective

Word History and Origins

Origin of operculum¹

1705–15; < New Latin, Latin: lid, cover, equivalent to oper ( īre ) to cover + -culum -cule ²

Word History and Origins

Origin of operculum¹

C18: via New Latin from Latin: lid, from operīre to cover

Example Sentences

When it approaches, the worms retract, vanish into their homes and slam shut an organ called an operculum — just like a door.

From New York Times

He startled periwinkles by tapping them on the operculum, a sort of trapdoor on their shell, and waited.

From New York Times

The genus Eucalyptus is named for its unusual floral structure derived from the Greek eu-, well, and kaluptos, covered, which refers to the operculum that covers the floral buds before anthesis.

From Nature

Taste information is then transmitted through several brain regions before arriving in the primary taste cortex, which is made up of the frontal operculum and the anterior insula.

From Scientific American

And then just like that, it evaporated into its burrow and slammed its operculum/trap-door closed.

From Scientific American