Word.ws English Dictionary

mustn't've

mustn't've contraction: must not have.

Contraction

mustn't've

  1. (colloquial, contraction) must not have
    • He isn't here. He mustn't've realised we'd be arriving so early.

Origin of mustn't've

mustn't + 've

Questions about mustn't've

What does mustn't've mean?
Mustn't've means must not have.
What part of speech is mustn't've?
Mustn't've is a contraction.

Words near mustn't've in the dictionary

  1. mustiphini
  2. mustiphinis
  3. Mustique
  4. mustn't
  5. mustn't grumble
  6. mustn't've
  7. mustna
  8. mustnae
  9. Musto
  10. Muston
  11. Mustons

Source and license

Adapted from Wiktionary: mustn't've (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.

Last updated:

Pronunciation audio from Wikimedia Commons, each file under its own free license: LL-Q1860 (eng)-Sapaa-mustn't've.wav.

Cite this entry: “mustn't've.” Word.ws, https://word.ws/mustn%27t%27ve. Based on Wiktionary, CC BY-SA 4.0.