acid-fast bacillus

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acid-fast bacillus (AFB)

a type of bacillus that resists decolorizing by acid after accepting a stain. Examples include Mycobacterium tuberculosis and M. leprae.

ac·id-fast ba·cil·lus

(AFB) (asid-fast bă-silŭs)
A type of bacterium that reacts in a given way when treated with an acid bath.

acid-fast bacillus

Abbreviation: AFB
A bacillus not readily decolorized by acids or other means when stained. Mycobacterium tuberculosis is an acid-fast bacillus.
See also: bacillus