From The Collaborative International Dictionary of English v.0.48:
Must \Must\, n. [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.).
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No fermenting must fills . . . the deep vats.
--Longfellow.
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2. [Cf. Musty.] Mustiness.
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From The Collaborative International Dictionary of English v.0.48:
Must \Must\ (m[u^]st), v. i. or auxiliary. [OE. moste, a pret.
generally meaning, could, was free to, pres. mot, moot, AS.
m[=o]ste, pret. m[=o]t, pres.; akin to D. moetan to be
obliged, OS. m[=o]tan to be free, to be obliged, OHG. muozan,
G. m["u]ssen to be obliged, Sw. m[*a]ste must, Goth.
gam[=o]tan 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.
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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.
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Likewise must the deacons be grave. --1 Tim. iii.
8.
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Morover, he [a bishop] must have a good report of
them which are without. --1 Tim. iii.
7.
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Note: 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.
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From The Collaborative International Dictionary of English v.0.48:
Must \Must\, v. t. & i.
To make musty; to become musty.
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From The Collaborative International Dictionary of English v.0.48:
must \must\, musth \musth\(m[u^]st), a. [Hind. mast intoxicated,
ruttish, fr. Skr. matta, p.p. of mad to rejoice, intoxicate.]
(Zool.)
Being in a condition of dangerous frenzy, usually connected
with sexual excitement; -- said of adult male elephants which
become so at irregular intervals, typicaly due to increased
testosterone levels. -- n.
(a) The condition of frenzy.
(b) An elephant in must.
[Webster 1913 Suppl. +PJC]