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epistasis

[ih-pis-tuh-sis]

noun, plural e·pis·ta·ses [ih-pis-tuh-seez] /ɪˈpɪs təˌsiz/.

Genetics. a form of interaction between nonallelic genes in which one combination of such genes has a dominant effect over other combinations.
Medicine/Medical.
  1. the stoppage of a secretion or discharge.
  2. a scum that forms on a urine specimen upon standing.

Origin of epistasis

First recorded in 1915–20, epistasis is from the Greek word epístasis stopping, stoppage. See epi-, stasis
Related formsep·i·stat·ic [ep-uh-stat-ik] /ˌɛp əˈstæt ɪk/, adjective
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019
British Dictionary definitions for epistasis

epistasis

noun

obsolete scum on the surface of a liquid, esp on an old specimen of urine
med the arrest or checking of a bodily discharge, esp bleeding
Also called: hypostasis genetics the suppression by a gene of the effect of another gene that is not its allele
Derived Formsepistatic (ˌɛpɪˈstætɪk), adjective

Word Origin for epistasis

C19: from Greek: a stopping, from ephistanai to stop, from epi- + histanai to put
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 epistasis
n.

medical Latin, from Greek epistasis "a stopping, stoppage," from epi "upon" (see epi-) + stasis "a stopping or standing" (see stasis).

Online Etymology Dictionary, © 2010 Douglas Harper
epistasis in Medicine

epistasis

[ĭ-pĭs′tə-sĭs]

n. pl. e•pis•ta•ses (-sēz′)

A film that forms over the surface of a urine specimen.
An interaction between nonallelic genes, especially an interaction in which one gene suppresses the expression of another.
The suppression of a bodily discharge or secretion.
Related formsep′i•stat′ic (ĕp′ĭ-stăt′ĭk) adj.
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.