must

Definitions

To be obliged or bound to do something by necessity, duty, or law.

Used to express a strong belief or logical certainty that something is the case.

Something that is essential, highly recommended, or required.

Examples

You must finish your homework before you go outside to play.

We must arrive at the airport at least two hours before the flight.

She must be exhausted after working such a long shift.

Synonyms

obligation requirement necessity duty essential imperative compulsion

Antonyms

option choice freedom nonessential unnecessary discretion volition