Quantcast
Merriam-Webster Logo
  • Dictionary
  • Thesaurus
  • Medical
  • Scrabble
  • Spanish Central
  • Learner's Dictionary

mustn't

play
\ˈmə-sənt\

Definition of mustn't

  1. :  must not



1741

First Known Use of mustn't

1741


MUSTN'T Defined for Kids

mustn't

play
\ˈmə-sənt\

Definition of mustn't for Students

  1. :  must not




Seen and Heard

What made you want to look up mustn't? Please tell us where you read or heard it (including the quote, if possible).

WORD OF THE DAY

to work hard

Get Word of the Day daily email!

WORD GAMES

Take a 3-minute break and test your skills!

image567572573

Which of these is a synonym of unctuous?

angry oily prompt maudlin
Name That Thing

Test your visual vocabulary with our 10-question challenge!

TAKE THE QUIZ
SCRABBLE® Sprint

Test Your Knowledge - and learn some interesting things along the way.

TAKE THE QUIZ