Must word meaning and definition

[verb] be obliged, required, or forced to; "She has to get her driver's license"
[verb] be likely or probable; "They have to be kidding"
[verb] be logically necessary

\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. 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. 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.
\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. ). No fermenting must fills . . . the deep vats. --Longfellow. 2. [Cf. {Musty}.] Mustiness.
\Must\, v. t. & i. To make musty; to become musty.
\Must\ (m[u^]st), n. [Hind. mast intoxicated, ruttish, fr. Skr. matta, p.p. of mad to rejoice, intoxicate.] (Zo["o]l.) Being in a condition of dangerous frenzy, usually connected with sexual excitement; -- said of adult male elephants which become so at irregular intervals. -- n.
(a) The condition of frenzy.
(b) An elephant in must.

Morse code: -- ..- ... -