acid-fast

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

adjective

resistant to decolorizing by acidified alcohol after staining.

Origin of acid-fast

First recorded in 1900–05

OTHER WORDS FROM acid-fast

ac·id-fast·ness, noun
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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

Medical 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.

Other words from acid-fast

acid-fast′ness n.
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.