operculum

American  

[oh-pur-kyuh-luhm] / oʊˈpɜr kjə ləm /

noun

opercula, plural operculums plural

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.

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operculum British  

/ 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 the bony plate in certain gastropods covering the opening of the shell when the body is withdrawn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

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operculum Scientific  

/ ō-pûr′kyə-ləm /

opercula plural

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.

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Other Word Forms

Derived Forms

• opercular
  adjective

Inflected Forms

Nouns

• opercula
  plural
• operculums
  plural

Etymology

Origin of operculum

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

Example Sentences

See Examples For:

operculum opercula

Amphibians also have an auricular operculum, which is an extra bone in the ear that transmits sounds to the inner ear.

From Textbooks ● Jan. 1, 2015

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 ● Jun. 10, 2014

The neural activity evoked by pictures of high-calorie food was stronger in specific parts of the brain — the bilateral insula and frontal operculum — than when low-calorie foods were viewed.

From Nature ● Jun. 25, 2012

If not preserved in an envelope the calyptra and operculum are very apt to fall off and become lost.

From Encyclopaedia Britannica, 11th Edition, Volume 13, Slice 3 "Helmont, Jean" to "Hernosand" by Various

Since the remainder of the posterior wall of the otic capsule consists of cartilage, meeting the exoccipital, it may be that the opisthotic becomes the operculum in frogs.

From The Ancestry of Modern Amphibia: A Review of the Evidence by Eaton, Theodore H. (Theodore Hildreth)

D—Ampullae likewise placed in sand which is contained in a box, of which the spouts from the opercula extend crosswise into ampullae placed under them.

From De Re Metallica, Translated from the First Latin Edition of 1556 by Agricola, Georgius

It was easy to see that the stones are thin and porous opercula, which have formed part of small univalve shells.

From Personal Narrative of Travels to the Equinoctial Regions of America, During the Year 1799-1804 — Volume 1 by Ross, Thomasina

C—Ampullae placed in the sand which is contained in a box, the spouts of which reach from the opercula into ampullae placed under them.

From De Re Metallica, Translated from the First Latin Edition of 1556 by Agricola, Georgius

The Potamides inhabit the mouths of rivers in warm latitudes, and are distinguishable from the marine Cerithia by their orbicular and multispiral opercula.

From The Student's Elements of Geology by Lyell, Charles, Sir

Some authors consider them to be jaws; others, opercula.

From Webster's Unabridged Dictionary by Webster, Noah