mustn't
AmericanUsage
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.
“The player mustn’t move, bend or break any growing or attached natural object,” Moir said.
From Los Angeles Times ● Jul. 17, 2026
"People have heard this sort of talk before only to be badly let down because nothing changes – Burnham mustn't repeat that mistake," he said.
From BBC ● Jun. 29, 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
She told them calmly, “Never mind, girls, this machine mustn’t be trifled with, but certainly is airworthy.”
From "A Thousand Sisters" by Elizabeth Wein
Definitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023
Idioms from The American Heritage® Idioms Dictionary copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.
