Dictionary
acid–fast
adjective ac·id–fast \ˈa-səd-ˌfast\
Definition of ACID-FAST
: not easily decolorized by acids
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First Known Use of ACID-FAST
1903
Medical Dictionary
acid–fast
adjective \ˈas-əd-ˌfast\
Medical Definition of ACID–FAST
: not easily decolorized by acids (as when stained)—used especially of bacteria and tissues
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