Cambridge Dictionaries online Cambridge Dictionaries online

The most popular online dictionary and thesaurus for learners of English

English definition of “must”

See all translations

must

modal verb  /mʌst, məst/ (must) us  

must modal verb (BE NECESSARY)

used to show that it is necessary or important that something happen in the present or future: Seeing what others have and she lacks, she believes that she must have more. We must not surprise them (= it is wrong, dangerous, or forbidden). If you say that you must do something, you can mean that you have a firm intention to do something in the future: I must call my sister later. Must is sometimes used for emphasis: I must admit I enjoy these movies.

must modal verb (PROBABLY)

used to show that something is likely, probable, or certain to be true: Death must be better than this. "It must have been fun." "No, it wasn’t."
(Definition of must modal verb from the Cambridge Academic Content Dictionary © 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

make believe

believing or imagining things that appear to be attractive or exciting, but are not real

Word of the Day

Lies, lies, lies!

by Kate Woodford,
February 25, 2015
​​​ According to sociologists (=people who study the relationships between people living in groups), we are good at lying. As a species, we have developed a remarkable ability to deceive each other (= persuade each other that something false is true). Being able to say things that are not true can help with

Read More 

showrooming noun

February 23, 2015
the activity of examining a product in a physical store and then making the purchase with an online retailer Amazon’s new smartphone is specifically designed to make showrooming fast and easy.

Read More