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.

---

operculum British  

/ əʊˈpɜːkjʊləm /

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 the bony plate in certain gastropods covering the opening of the shell when the body is withdrawn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

---

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

Foot large and broad; eyes at base of 517 tentacles; operculum horny.

From Encyclopaedia Britannica, 11th Edition, Volume 11, Slice 5 "Gassendi, Pierre" to "Geocentric" by Various

Shell spiral; mantle and shell with an anterior fissure; two ctenidia; a horny operculum.

From Encyclopaedia Britannica, 11th Edition, Volume 11, Slice 5 "Gassendi, Pierre" to "Geocentric" by Various

From the remarks on this genus, made at Plate 103, the fact of their opercula being either shelly or horny, is sufficiently established.

From Zoological Illustrations, Volume II or Original Figures and Descriptions of New, Rare, or Interesting Animals by William Swainson

A still more highly endowed relation spins a similar fabric, upon which are loosely agglutinated numbers of small dead shells, grit, and even opercula a quarter of an inch in diameter.

From My Tropic Isle by E. J. (Edmund James) Banfield

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 Sir Charles Lyell

The tails were only half the original length, all had well-developed hind-legs, some with toes, but the fore-legs were beneath the opercula, not projecting from the surface.

From Hormones and Heredity by J. T. Cunningham

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

From Webster's Unabridged Dictionary by Noah Webster

Random Word

Spin the wheel and learn a new word!

---