• synonyms


[kok-sahy, -see]
  1. plural of coccus.
  2. coccidioidomycosis.
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[kok-uh s]
noun, plural coc·ci [kok-sahy, -see] /ˈkɒk saɪ, -si/.
  1. Bacteriology. a spherical bacterium.
  2. Botany. one of the carpels of a schizocarp.
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Origin of coccus

1755–65; < New Latin < Greek kókkos grain, seed, berry
Related formscoc·cal, coc·cic [kok-sik] /ˈkɒk sɪk/, adjectivecoc·cous, adjective
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018

Examples from the Web for cocci

Historical Examples

  • Nearly all cocci are immotile, while the bacilli may or may not be.

    Outlines of Dairy Bacteriology, 8th edition

    H. L. Russell

  • By this orifice the cocci are enabled to escape from the detached scales.

  • As a result there may be a variety of cell groupings among the cocci.

    The Fundamentals of Bacteriology

    Charles Bradfield Morrey

  • A genus of schizomycetes in which the cocci are arranged in strings or in chains.

  • Tetra- (in words of Greek composition), four; as, Tetracoccous, of four cocci.

British Dictionary definitions for cocci


  1. the plural of coccus
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noun plural -ci (-saɪ)
  1. any spherical or nearly spherical bacterium, such as a staphylococcusCompare bacillus (def. 1), spirillum (def. 1)
  2. the part of a fruit that contains one seed and separates from the whole fruit at maturity
  3. any of the scale insects of the genus Coccus
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Derived Formscoccoid, coccal or coccic (ˈkɒksɪk), adjectivecoccous, adjective

Word Origin

C18: from New Latin, from Greek kokkos berry, grain
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Word Origin and History for cocci


spherical-shaped bacteria, plural of Latin coccus, from Greek kokkos "berry" (see cocco-).

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1763 as an insect genus (including the cochineal bug); 1883 as a type of bacterium, from Greek kokkos "grain, seed, berry" (see cocco-).

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Online Etymology Dictionary, © 2010 Douglas Harper

cocci in Medicine


n. pl. coc•ci (kŏksī, kŏkī)
  1. A bacterium of round, spheroidal, or ovoid form.
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Related formscoccoid′ (kŏkoid′) null adj.
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.

cocci in Science


Plural cocci (kŏksī, kŏkī)
  1. Any of various bacteria having a round or ovoid form such as streptococcus or staphylococcus, usually grouped in chains.
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The American Heritage® Science Dictionary Copyright © 2011. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.