mid-15c., from Middle French militaire (14c.), from Latin militaris "of soldiers or war, of military service, warlike," from miles (genitive militis) "soldier," 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." Related: Militarily. Old English had militisc, from Latin. Military-industrial complex coined 1961 in farewell speech of U.S. president Dwight D. Eisenhower.
"soldiers generally," 1757, from military (adj.). Earlier, "a military man" (1736).