must modal verb, noun Meaning in Cambridge English Dictionary
Cambridge Dictionaries online Cambridge Dictionaries online

The most popular online dictionary and thesaurus for learners of English

Meaning of "must" - English Dictionary

See all translations

mustmodal verb

uk   us   strong /mʌst/ weak /məst/ /məs/

must modal verb (NECESSARY)

A2 used to show that it is necessary or very important that something happens in the present or future: Meat must be cooked thoroughly. I must get some sleep. You mustn't show this letter to anyone else. Luggage must not be left unattended (= it is against the rules).formal Must you leave so soon?formal "Must I sign this?" "Yes, you must." If you say that you must do something, you mean that you strongly intend to do something in the future: I must phone my sister. We must get someone to fix that wheel. I mustn't bite my nails. used for emphasis: I must say, you're looking extremely well. I must admit, I wasn't looking forward to it.B1 If you tell someone else that they must do something pleasant, you are emphasizing that you think it is a good idea to do that: You must come and stay with us for the weekend. We must meet for lunch soon.
More examples

must modal verb (PROBABLY)

B2 used to show that something is very likely, probable, or certain to be true: Harry's been driving all day - he must be tired. There's no food left - we must have eaten it all. When you got lost in the forest you must have been very frightened. "You must know Frank." "No, I don't."
More examples

mustnoun [C]

uk   us   strong /mʌst/ weak /məst/ /məs/ informal
something that is necessary: If you live in the country a car is a must.
(Definition of must modal verb, noun from the Cambridge Advanced Learners Dictionary & Thesaurus © Cambridge University Press)
What is the pronunciation of must?
Add Cambridge dictionaries to your browser to your website

Definitions of “must” in other dictionaries

Word of the Day
field event

a sports event in which athletes take part one after the other rather than racing or competing together

Word of the Day

Are you a glass-half-full person? (Everyday Idioms)
Are you a glass-half-full person? (Everyday Idioms)
by Kate Woodford,
July 29, 2015
A reader of this blog recently asked for a post on idioms that are used in everyday English. This seemed like a reasonable request. After all, if you are going to make the effort to learn a set of English idioms, you want those idioms to be useful. The question, then, was

Read More 

exoskeleton noun
exoskeleton noun
July 27, 2015
a robotic device which goes around the legs and part of the body of a person who cannot walk and allows them to move independently and in an upright position The device, known as an exoskeleton, is strapped to the outside of a person’s limbs and can then be controlled by them.

Read More