late 14c., "to come to an end," also "to settle, decide," from O.Fr. determiner (12c.), from L. determinare "set limits to," from de- "off" + terminare "to mark the end or boundary," from terminus "end, limit." Sense of "coming to a firm decision" (to do something) is from mid-15c. Determinism is 1846 in theology (lack of free will); 1876 in general sense of "the doctrine that everything that happens is determined by a necessary chain of causation."