英语词源字典 - 在线词源网站

off (adv.)[off 词源字典]: by c. 1200 as an emphatic form of Old English of (see of), employed in the adverbial use of that word. The prepositional meaning "away from" and the adjectival sense of "farther" were not firmly fixed in this variant until 17c., but once they were they left the original of with the transferred and weakened senses of the word. Meaning "not working" is from 1861. Off the cuff (1938) is from the notion of speaking from notes written in haste on one's shirt cuffs. Off the rack (adj.) is from 1963; off the record is from 1933; off the wall "crazy" is 1968, probably from the notion of a lunatic "bouncing off the walls" or else in reference to carom shots in squash, handball, etc.[off etymology, off origin, 英语词源]
off (v.): "to kill," 1930, from off (adv.). Earlier verbal senses were "to defer" (1640s), "to move off" (1882). Related: Offed.
off-and-on (adv.): "intermittently," 1530s; see off (adv.) + on. As an adjective from 1580s.
off-base (adv.): "unawares," 1936, American English, from off (adv.) + base (n.); a figurative extension from baseball sense of "not in the right position" (1898), from notion of a baserunner being picked off while taking a lead.
off-beat (adj.): also offbeat, "unusual," 1938, from off (adv.) + beat (n.). From earlier sense in reference to from music rhythm (1927).
off-Broadway (adj.): 1953, "experimental theater productions in New York City," from off (adv.) + Broadway. Even more experimental off-off-Broadway is attested from 1967.
off-camera (adj.): 1944, from off (adv.) + camera.
off-chance (n.): 1861, from off (adv.) + chance (n.).
off-color (adj.): 1858, from off (adv.) + color (n.); originally used of gems; figurative extension to "of questionable taste, risqué" is American English, 1867.
off-colour (adj.): see off-color.
off-duty (adj.): 1743, from off (adv.) + duty.
off-hand (adv.): also offhand, 1690s, "at once, straightway," from off (adv.) + hand (n.). Probably originally in reference to shooting without a rest or support. Hence, of speech or action, "unpremeditated" (1719). Related: Off-handed; off-handedly.
off-key (adj.): 1920, from off (adv.) + musical sense of key (n.1). Figurative sense is from 1943.
off-limits (adj.): "forbidden," by 1881, U.S. military academies jargon, from off (adv.) + limit (n.). Earlier (1857) it was applied to cadets, etc., who were in violation of the limitations on their movement and behavior.
off-line (adj.): 1926, of railroads; 1950, of computers; from off (adv.) + line (n.).
off-load (v.): "unload," 1850, from off (adv.) + load (v.). Originally S.African, on model of Dutch afladen.
off-peak (adj.): 1906, originally in reference to electrical systems, from off (adv.) + peak (n.).
off-putting: 1570s, "procrastinating," from off (adv.) + put (v.). Meaning "creating an unfavorable impression" is first recorded 1894.
off-ramp (n.): 1954, from off (adv.) + ramp (n.).
off-road (adj.): 1949, from off (adv.) + road.