[ oh-pur-kyuh-luhm ]
/ o蕣藞p蓽r ky蓹 l蓹m /
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noun, plural o路per路cu路la [oh-pur-kyuh-luh], /o蕣藞p蓽r ky蓹 l蓹/, o路per路cu路lums.
Botany, Zoology. a part or organ serving as a lid or cover, as a covering flap on a seed vessel.
  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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鈥淲as鈥 is used for the indicative past tense of 鈥渢o be,鈥 and 鈥渨ere鈥 is only used for the subjunctive past tense.

Origin of operculum

1705鈥15; <New Latin, Latin: lid, cover, equivalent to oper(墨re) to cover + -culum-cule2


o路per路cu路lar, adjective
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, 漏 Random House, Inc. 2022

How to use operculum in a sentence

British Dictionary definitions for operculum

/ (蓹蕣藞p蓽藧kj蕣l蓹m) /

noun plural -la (-l蓹) or -lums
  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 the bony plate in certain gastropods covering the opening of the shell when the body is withdrawn
botany the covering of the spore-bearing capsule of a moss
biology any other covering or lid in various organisms

Derived forms of operculum

opercular or operculate (蓹蕣藞p蓽藧kj蕣l瑟t, -藢le瑟t), adjective

Word Origin for operculum

C18: via New Latin from Latin: lid, from oper墨re to cover
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition 漏 William Collins Sons & Co. Ltd. 1979, 1986 漏 HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Medical definitions for operculum

[ 艒-p没rky蓹-l蓹m ]

n. pl. o鈥er鈥u鈥ums
Something resembling a lid or cover.
The portions of the frontal, parietal, and temporal lobes covering the insula.
The mucus sealing the endocervical canal of the uterus after conception.
The attached flap in cases of torn retinal detachment.
The mucosal flap partially or completely covering an unerupted tooth.

Other words from operculum

o鈥ercu鈥ar (-l蓹r) adj.
The American Heritage庐 Stedman's Medical Dictionary Copyright 漏 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.

Scientific definitions for operculum

[ 艒-p没rky蓹-l蓹m ]

Plural opercula operculums
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.
The American Heritage庐 Science Dictionary Copyright 漏 2011. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.