Etimology
From Middle English moste ("must", literally, "had to", the past tense of Middle English moten (“to have to”)), from Old English mōste (“had to”), 1st & 3rd person singular past tense of mōtan (“to be allowed, be able to, have the opportunity to, be compelled to, must, may”), from Proto-Germanic *mōtaną. Cognate with Dutch moest (“had to”), German musste (“had to”), Swedish måste (“must, have to, be obliged to”). More at mote.
verb
must (third-person singular simple present must, no present participle, simple past must, no past participle)
(modal auxiliary, defective) To do as a requirement; indicates that the sentence subject is required as an imperative or directive to execute the sentence predicate, with failure to do so resulting in a failure or negative consequence.
(modal auxiliary, defective) To do with certainty; indicates that the speaker is certain that the subject will have executed the predicate.
(modal auxiliary, defective) Used to indicate that something is very likely, probable, or certain to be true.
Examples
You must arrive in class on time.
This door handle must be rotated fully.
Arise, and go into the city, and it shall be told thee what thou must do.
If it has rained all day, it must be very wet outside.
You picked one of two, and it wasn't the first: it must have been the second.
The children must be asleep by now.
noun
must (plural musts)
Something that is mandatory or required.
Examples
Synonyms: imperative, necessity
Antonym: no-no
Hyponyms: must-do, must-have, must-see
If you're trekking all day, a map is a must.
Etimology
From Middle English must, from Old English must and Old French must, most, both from Latin mustum.
noun
must (countable and uncountable, plural musts)
The property of being stale or musty.
Something that exhibits the property of being stale or musty.
Fruit juice that will ferment or has fermented, usually from grapes.
Examples
No sweet grape lies hidden here in the shade of its vine-leaves,No fermenting must fills and o'erflows the deep vats.
verb
must (third-person singular simple present musts, present participle musting, simple past and past participle musted)
(transitive) To make musty.
(intransitive) To become musty.
Etimology
From Persian مست (mast, “drunk, inebriated”), from Middle Persian 𐭬𐭮𐭲 (mast).
noun
must (countable and uncountable, plural musts)
Alternative form of musth
Examples
It was not, of course, a wild elephant, but a tame one which had gone ‘must’.