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mustn't

American  
[muhs-uhnt] / ˈmʌs ənt /
  1. contraction of must not.


Usage

See contraction.

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

See Examples For:

“The player mustn’t move, bend or break any growing or attached natural object,” Moir said.

From Los Angeles Times Jul. 17, 2026

"If I went into my job and I wasn't threatened on a day I would come out and go: 'Oh I mustn't have done my job today.'"

From BBC May 13, 2026

But "we mustn't give in to this siren song," warned Bernard Jullien, an automotive industry specialist at the University of Bordeaux.

From Barron's May 8, 2026

I’m sad that I mustn’t climb tall ladders anymore, per an agreement with Karen.

From The Wall Street Journal Dec. 4, 2025

Laura is terrified she is going to say something she mustn't.

From "How the García Girls Lost Their Accents" by Julia Alvarez

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