1837, "detailed list of dishes to be served at a banquet or meal," from French menu de repas "list of what is served at a meal," from French menu (adj.) "small, detailed" (11c.), from Latin minutus "small," literally "made smaller," past participle of minuere "to diminish," from root of minus "to diminish" (from PIE root *mei- (2) "small"). Computer sense of "list of options displayed on a screen" is by 1967, from the expanded sense of "any detailed list," which is attested by 1889.
"kind of porridge; meal boiled in water or milk until it forms a thick, soft mass," 1670s, in the American colonies, a variant of mash (n.) "soft mixture." Meaning "anything soft and thick" is attested from 1824.
late 14c., "one who serves" in any capacity, agent noun from serve (v.). Especially "an attendant at a meal" (mid-15c.). By 1580s in sports. The meaning "that which is used in serving" is by c. 1600; the computing sense is by 1992.