Word.ws English Dictionary

acid-fast

acid-fast adjective: retaining stain when treated with an acidic solution.

Adjective

acid-fast (comparative more acid-fast, superlative most acid-fast)

  1. Retaining stain when treated with an acidic solution.

Forms of acid-fast

comparativemore acid-fast
superlativemost acid-fast

Words formed from acid-fast

  • acid-fast bacillus

Questions about acid-fast

What does acid-fast mean?
Acid-fast means retaining stain when treated with an acidic solution.
What part of speech is acid-fast?
Acid-fast is an adjective.

Words near acid-fast in the dictionary

  1. acid-base equilibriums
  2. acid-base indicator
  3. acid-base indicators
  4. acid-base pair
  5. acid-base pairs
  6. acid-fast
  7. acid-fastness
  8. acid-forming
  9. acid-free
  10. acid-proof
  11. acid-resistant

Source and license

Adapted from Wiktionary: acid-fast (page history and authors). Text available under the Creative Commons Attribution-ShareAlike 4.0 license. Word.ws reformatted the entry and added links. Wiktionary data of 2026-09-02.

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