Meaning of MUST in English

I. (|)məs(t) verb

( present & past all persons must )

Etymology: Middle English moste (past indicative & subjunctive of moten to be allowed to, be able to, have to), from Old English mōste, past indicative & subjunctive of mōtan to be allowed to, be able to, have to; akin to Old Saxon mōtan to have cause for, be obliged to, have to, Old High German muozan to be allowed to, be able to, have to, Gothic ga motan to have room, fit; basic meaning: to have allotted to one; derivative from the stem of Old English metan to measure — more at mete

verbal auxiliary


a. : is commanded or requested to

you must stop that noise

you must hear my side of the story

he must be made to obey

I told him what he must do

b. : is urged to : ought by all means to

you must read that book

you must come to visit us soon

2. : is compelled by physical necessity to

man must eat to live

: is required by immediate or future need or purpose to

we must hurry if we want to catch the bus

must you take all that luggage along

if you wished to see it you must queue — Leslie Eytle

3. : is obliged to : is compelled by social considerations to

I must say you're looking much better

I must admit your plane's safer

realized that he must say nothing about it

4. : is required by law, custom, or moral conscience to

we must obey the rules

you must respect your father's wishes

the present government must go … for it is too gross a scandal — John Buchan


a. : is compelled by resolve : is determined to

if you must go at least wait till the storm is over

b. : is unreasonably or perversely compelled to

I was planning a surprise for you, if you must know

why must you be so stubborn

why must it always rain on weekends

6. : is logically inferred or supposed to

he must be out of his mind to say that

it must be nearly dinner time

he must have done it, no one else was there

it must have been the coffee that kept me awake

7. : is compelled by fate or by natural law to

what must be will be

the innocent must suffer with the guilty

three men who must leave their Queen on her death bed — Edith Sitwell

a woman must have children to love — Edith Wharton

8. : was presumably certain to : would surely or necessarily : was bound to

if he had really been there I must have seen him

buffalo … beat out a track where human beings must have measurably failed — S.C.Williams

must have fallen had the railing not been there

my rifle was slung on my back … else I must have lost it — Lea MacNally

9. dialect : may , shall — used chiefly in questions

must I bring in the soup now

intransitive verb

1. : is obliged or compelled

when Duty whispers low “thou must ” the youth replies “I can” — R.W.Emerson

shoot if you must this old gray head — J.G.Whittier

2. archaic : ought to go : is obliged to go — used with adverb or adverbial phrase

I must to Coventry — Shakespeare

I must now to breakfast — John Buchan

Synonyms: see ought

II. ˈməst noun

( -s )

Usage: often attributive


a. : an imperative need or duty : obligation , requirement

in highly competitive modern industry, technological progress is a must — Annual Report General Motors Corp.

told Republican leadership that the bill was a must — New York Times

less plagued … by rigid musts — Walter de la Mare

b. : an indispensable item : essential , necessity

a raincoat is an absolute must — Richard Joseph

facility, capacity and dependability of project equipment are musts — Military Engineer

specifically : a priority item marked for inclusion without fail in a particular edition of a newspaper

2. : something that deserves attention because of its outstanding merit

this is a lovely place, a real must for visitors — Richard Joseph

for the thrill of being close to the original … the volume is a must — Louis Marder

III. noun

( -s )

Etymology: Middle English, from Old English, from Latin mustum, from neuter of mustus young, fresh, new; perhaps akin to Greek mysos spot, stain, defect, Old Irish mossach dirty, Old English mos moss — more at moss


a. : the juice of grapes or other fruit before and during fermentation

b. : the juice in combination with the pulp and skins of the crushed fruit

2. dialect England : the pomace of apples or pears often used as fodder for livestock

IV. noun

( -s )

Etymology: Middle French, alteration of musc — more at musk

1. : musk

2. : mustiness , mold

the dust and must of a decade — Marcia Davenport

V. intransitive verb

: to become musty or moldy

transitive verb

archaic : to powder (the hair) with musk


variant of musth

Webster's New International English Dictionary.      Новый международный словарь английского языка Webster.