Word.ws English Dictionary

mustn't

/ˈmʌs.n̩t/

mustn't verb: must not (negative auxiliary); used to indicate that something is forbidden or, in a tag question, that something is not necessary.

Verb

mustn't

  1. (uncommon) Must not (negative auxiliary); used to indicate that something is forbidden or, in a tag question, that something is not necessary.
    • You mustn't blame yourself for this tragedy.
    • We must go, mustn't we?

Origin of mustn't

From must + -n't.

Phrases with mustn't

Questions about mustn't

What does mustn't mean?
Mustn't means must not (negative auxiliary); used to indicate that something is forbidden or, in a tag question, that something is not necessary.
What part of speech is mustn't?
Mustn't is a verb.
How do you pronounce mustn't?
Mustn't is pronounced /ˈmʌs.n̩t/.

Words near mustn't in the dictionary

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

Source and license

Adapted from Wiktionary: mustn't (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: en-US mustn't.ogg.

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