mustn't've

contraction

must not have

“He isn't here. He mustn't've realised we'd be arriving so early.”

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Meanings

contraction
  1. colloquialcontractionmust not have

    He isn't here. He mustn't've realised we'd be arriving so early.

Origin

mustn't + 've

Full word history & related roots →
Cite this entry
APA

mustn't've. (n.d.). In WatkinsX Dictionary. Retrieved November 3, 2026, from https://dictionary.watkinsx.com/word/mustn't've

MLA

“mustn't've.” WatkinsX Dictionary, https://dictionary.watkinsx.com/word/mustn't've. Accessed November 3, 2026.

Chicago

WatkinsX Dictionary, s.v. “mustn't've,” accessed November 3, 2026, https://dictionary.watkinsx.com/word/mustn't've.

Source: mustn't've on Wiktionary, CC BY-SA 4.0.