must

1
[ muhst ]
See synonyms for: mustmuster on Thesaurus.com

auxiliary verb
  1. to be obliged or bound to by an imperative requirement: I must keep my word.

  2. to be under the necessity to; need to: Animals must eat to live.

  1. to be required or compelled to, as by the use or threat of force: You must obey the law.

  2. to be compelled to in order to fulfill some need or achieve an aim: We must hurry if we're to arrive on time.

  3. to be forced to, as by convention or the requirements of honesty: I must say, that is a lovely hat.

  4. to be or feel urged to; ought to: I must buy that book.

  5. to be reasonably expected to; is bound to: It must have stopped raining by now. She must be at least 60.

  6. to be inevitably certain to; be compelled by nature: Everyone must die.

verb (used without object)
  1. to be obliged; be compelled: Do I have to go? I must, I suppose.

  2. Archaic. (sometimes used with ellipsis of go, get, or some similar verb readily understood from the context): We must away.

adjective
  1. necessary; vital: A raincoat is must clothing in this area.

noun
  1. something necessary, vital, or required: This law is a must.

Origin of must

1
First recorded before 900; Middle English most(e), Old English mōste (past tense); cognate with German musste. See mote2

synonym study For must

1. Must, ought, should express necessity or duty. Must expresses necessity or compulsion: I must attend to those patients first. Soldiers must obey orders. Ought (weaker than must ) expresses obligation, duty, desirability: You ought to tell your mother. Should expresses obligation, expectation, or probability: You are not behaving as you should. Children should be taught to speak the truth. They should arrive at one o'clock.

Words Nearby must

Other definitions for must (2 of 4)

must2
[ muhst ]

noun
  1. new wine; the unfermented juice as pressed from the grape or other fruit.

Origin of must

2
First recorded before 900; Middle English, Old English, from Latin mustum, short for vīnum mustum “new wine”

Other definitions for must (3 of 4)

must3
[ muhst ]

noun
  1. mold; moldiness; mustiness: a castle harboring the must of centuries.

Origin of must

3
First recorded in 1595–1605; back formation from musty1

Other definitions for must (4 of 4)

must4
[ muhst ]

noun
  1. musk, especially a powder made from musk.

verb (used with object)
  1. to powder (the hair).

Origin of must

4
First recorded in 1480–90; earlier moist, from Middle French must, variant of musc; see origin at musk

Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2024

How to use must in a sentence

  • All of a sudden the Writer and the Sketcher found themselves thrust into the presence of He-who-must-be-obeyed.

  • All of a sudden, with one accord, they put to the Sphinx the question that He-who-must-be-obeyed had asked them.

  • Had not He-who-must-be-obeyed ordered them to seek out the solution of the Great Conundrum?

  • The starching, the fluting, the ironing, all take precious hours that might be employed upon some of the must-haves.

  • It was that terrible once-on-board-the-lugger-and-the-girl-is-mine-I-must-and-shall-possess-her feeling in its most acute form.

    The Limit | Ada Leverson

British Dictionary definitions for must (1 of 5)

must1

/ (mʌst, unstressed məst, məs) /


verb(takes an infinitive without to or an implied infinitive)
  1. used as an auxiliary to express obligation or compulsion: you must pay your dues . In this sense, must does not form a negative. If used with a negative infinitive it indicates obligatory prohibition

  2. used as an auxiliary to indicate necessity: I must go to the bank tomorrow

  1. used as an auxiliary to indicate the probable correctness of a statement: he must be there by now

  2. used as an auxiliary to indicate inevitability: all good things must come to an end

  3. (used as an auxiliary to express resolution)

    • on the part of the speaker when used with I or we: I must finish this

    • on the part of another or others as imputed to them by the speaker, when used with you, he, she, they, etc: let him get drunk if he must

  4. (used emphatically) used as an auxiliary to express conviction or certainty on the part of the speaker: he must have reached the town by now, surely; you must be joking

  5. (foll by away) used with an implied verb of motion to express compelling haste: I must away

noun
  1. an essential or necessary thing: strong shoes are a must for hill walking

Origin of must

1
Old English mōste past tense of mōtan to be allowed, be obliged to; related to Old Saxon mōtan, Old High German muozan, German müssen

British Dictionary definitions for must (2 of 5)

must2

/ (mʌst) /


noun
  1. mustiness or mould

Origin of must

2
C17: back formation from musty

British Dictionary definitions for must (3 of 5)

must3

/ (mʌst) /


noun
  1. the newly pressed juice of grapes or other fruit ready for fermentation

Origin of must

3
Old English, from Latin mustum new wine, must, from mustus (adj) newborn

British Dictionary definitions for must (4 of 5)

must4

/ (mʌst) /


noun
  1. a variant spelling of musth

British Dictionary definitions for must- (5 of 5)

must-

combining form
  1. indicating that something is highly recommended or desirable: a must-see film; this season's must-haves

Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Other Idioms and Phrases with must

must

see a must; show must go on.

The American Heritage® Idioms Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.