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definitions

asymptomatic

[ey-simp-tuh-mat-ik, ey-simp-]
adjective
  1. showing no evidence of disease.

Origin of asymptomatic

First recorded in 1930–35; a-6 + symptomatic
Related formsa·symp·to·mat·i·cal·ly, adverb
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
British Dictionary definitions for asymptomatic

asymptomatic

adjective
  1. (of a disease or suspected disease) without symptoms; providing no subjective evidence of existence
Derived Formsasymptomatically, adverb
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 asymptomatic
adj.

"without symptoms," 1856, from a-, privative prefix, + symptomatic.

Online Etymology Dictionary, © 2010 Douglas Harper
asymptomatic in Medicine

asymptomatic

[ā′sĭmp-tə-măt′ĭk]
adj.
  1. Exhibiting or producing no symptoms.
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.