Meaning of MUST in English

I. məs(t), ˈməst verb

( present & past all persons must )

Etymology: Middle English moste, from Old English mōste, past indicative & subjunctive of mōtan to be allowed to, have to; akin to Old High German muozan to be allowed to, have to

Date: before 12th century

verbal auxiliary


a. : be commanded or requested to

you must stop

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

you must read that book

2. : be compelled by physical necessity to

one must eat to live

: be required by immediate or future need or purpose to

we must hurry to catch the bus


a. : be obliged to : be compelled by social considerations to

I must say you're looking well

b. : be required by law, custom, or moral conscience to

we must obey the rules

c. : be determined to

if you must go at least wait for me

d. : be unreasonably or perversely compelled to

why must you argue

4. : be logically inferred or supposed to

it must be time

5. : be compelled by fate or by natural law to

what must be will be

6. : was or were presumably certain to : was or were bound to

if he did it she must have known

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

intransitive verb

archaic : to be obliged to go

I must to Coventry — Shakespeare

II. ˈməst noun

Date: 1616

1. : an imperative need or duty : requirement

2. : an indispensable item : essential

exercise is a must

III. noun

Etymology: Middle English, from Old English, from Latin mustum

Date: before 12th century

: the expressed juice of fruit and especially grapes before and during fermentation ; also : the pulp and skins of the crushed grapes

IV. noun

Etymology: Middle English (Scots) moist, from Middle French must, alteration of musc musk

Date: 15th century

1. : musk

2. : mold , mustiness

Merriam-Webster's Collegiate English vocabulary.      Энциклопедический словарь английского языка Merriam Webster.