definitions

acid-fast

[ as-id-fast, -fahst ]
/ ˈæs ɪdˌfæst, -ˌfɑst /
|

adjective

resistant to decolorizing by acidified alcohol after staining.

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Nearby words

acid washing, acid-ash diet, acid-base balance, acid-base equilibrium, acid-base indicator, acid-fast, acid-forming, acid-head, acid-loving, acid-phosphatase test for semen, acid-reflux test

Origin of acid-fast

First recorded in 1900–05
Related formsac·id-fast·ness, noun
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019

Examples from the Web for acid-fast

British Dictionary definitions for acid-fast

acid-fast

adjective

(of bacteria and tissues) resistant to decolorization by mineral acids after staining
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

Medicine definitions for acid-fast

acid-fast

adj.

Of or relating to bacteria that are not decolorized by an acidic alcohol solution after they have been stained.
Related formsac′id-fast′ness n.
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.