Also found in: Dictionary, Thesaurus, Encyclopedia.
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.
Medical Dictionary for the Health Professions and Nursing © Farlex 2012
acid-fast bacillusAbbreviation: AFB
A bacillus not readily decolorized by acids or other means when stained. Mycobacterium tuberculosis is an acid-fast bacillus.
See also: bacillus
Medical Dictionary, © 2009 Farlex and Partners