[ as-kuhs ]
/ ˈæs kəs /
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noun, plural as·ci [as-ahy, -kahy, -kee]. /ˈæs aɪ, -kaɪ, -ki/. Mycology.
the sac in ascomycetes in which the sexual spores are formed.
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Origin of ascus

1820–30; <New Latin <Greek askós bag, sac

Words nearby ascus

Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2022

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British Dictionary definitions for ascus

/ (ˈæskəs) /

noun plural asci (ˈæsaɪ, ˈæskaɪ)
a saclike structure that produces (usually) eight ascospores during sexual reproduction in ascomycetous fungi such as yeasts and mildews

Word Origin for ascus

C19: from New Latin, from Greek askos bag
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

Medical definitions for ascus

[ ăskəs ]

n. pl. as•ci (ăsī′, -kī′)
A membranous, often club-shaped structure in which typically eight spores are formed through sexual reproduction of ascomycetes.
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.

Scientific definitions for ascus

[ ăskəs ]

Plural asci (ăsī′, -kī′)
A membranous, often club-shaped structure inside which ascospores are formed through sexual reproduction in species of the fungi known as ascomycetes. The ascus is unique to ascomycetes and distinguishes them from other kinds of fungi. Asci are formed when two hyphae that are sexually compatible conjugate. Each ascus typically develops eight ascospores. Asci swell at maturity until they burst, shooting the ascospores into the air.
The American Heritage® Science Dictionary Copyright © 2011. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.