must intransitive verb or auxiliary verb [OE. moste, a pret. generally meaning, could, was free to, pres. mot, moot, AS. mōste, pret. mōt, pres.; akin to D. moetan to be obliged, OS. mōtan to be free, to be obliged, OHG. muozan, G. müssen to be obliged, Sw. måste must, Goth. gamōtan to have place, have room, to able; of unknown origin.]

1. To be obliged; to be necessitated; – expressing either physical or moral necessity; as, a man must eat for nourishment; we must submit to the laws.

2. To be morally required; to be necessary or essential to a certain quality, character, end, or result; as, he must reconsider the matter; he must have been insane.

Likewise must the deacons be grave. 1 Tim. iii. 8.

Morover, he [a bishop] must have a good report of them which are without. 1 Tim. iii. 7.

☞ The principal verb, if easily supplied by the mind, was formerly often omitted when must was used; as, I must away.

“I must to Coventry.” Shak.

Must noun [AS. must, fr. L. mustum (sc. vinum), from mustus young, new, fresh. Cf. Mustard.]

1. The expressed juice of the grape, or other fruit, before fermentation.

“These men ben full of must.” Wyclif (Acts ii. 13.)

No fermenting must fills . . . the deep vats. Longfellow.

2. [Cf. Musty.] Mustiness.

Must transitive or intransitive verb To make musty; to become musty.