mid-14c., "keep back or in store for future use;" late 14c., "keep as one's own," from Old French reserver "set aside, withhold" (12c.) and directly from Latin reservare "keep back, save up; retain, preserve," from re- "back" (see re-) + servare "to keep, save, preserve, protect" (from PIE root *ser- (1) "to protect"). Meaning "to book" is from 1935. Related: Reserved; reserving.
mid-15c., militari, "pertaining to or befitting soldiers; used, done, or brought about by soldiers," from Old French militaire (14c.) and directly from Latin militaris "of soldiers or war, of military service, warlike," from miles (genitive militis) "soldier," a word of unknown origin.
Perhaps ultimately from Etruscan, or else meaning "one who marches in a troop," and thus connected to Sanskrit melah "assembly," Greek homilos "assembled crowd, throng." De Vaan writes, "It is tempting to connect mīlia [pl.] 'thousand(s)', hence *mīli-it- 'who goes with/by the thousand' ...." Related: Militarily. Old English had militisc, from Latin.
Military police is from 1827. Military age, at which one becomes liable to military service, is by 1737. Military-industrial complex was coined 1961 in the farewell speech of U.S. president Dwight D. Eisenhower.
"soldiers generally," 1757, from military (adj.); commonly only with the definite article. Earlier, "a military man" (1736).
1610s, "something stored up," from reserve (v.) or from French réserve, a back-formation from reserver "set aside, withhold," from Latin reservare "keep back, save up; retain, preserve," from re- "back" (see re-) + servare "to keep, save, preserve, protect" (from PIE root *ser- (1) "to protect").
Meaning "self-imposed restraint on freedom of words or actions; habit of keeping back the feelings" is from 1650s. The meaning "district or place set apart for some particular use" is by 1805. The sense of "amount of capital kept on hand to meet probable expenses or demand" is by 1866. That of "amount of natural resources known to exist in a particular region" is by 1912. As an adjective, "kept in reserve," by 1719.
The military sense of "body of troops withheld from action to serve as reinforcements, etc." is from 1640s; that of "national emergency defense or auxiliary military force" (reserves) is by 1866.
late 14c., from Anglo-French subsidie, Old French subside "help, aid, assistance, contribution," from Latin subsidium "a help, aid, assistance, (military) reinforcements, troops in reserve," from subsidere "to settle down, stay, remain" (see subside).
1540s, from Latin subsidiarius "belonging to a reserve, of a reserve, reserved; serving to assist or supplement," from subsidium "a help, aid, relief, troops in reserve" (see subsidy). As a noun, c. 1600, "subsidiary thing." In Latin the word was used as a noun meaning "the reserve."
"a standby, a reserve," 1952; see back up (v.). Specific reference to computing is from 1965.
"soldier who belongs to the reserves," 1872, from French réserviste, from reserver (see reserve (v.)).