off (prep., adv.)

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 "extemporaneously, without preparation" (1938) is from the notion of speaking from notes written in haste on one's shirt cuffs. In reference to clothing, off the rack (adj.) "not tailored, not made to individual requirements, ready-made" is by 1963, on the notion of buying it from the rack of a clothing store; off the record "not to be publicly disclosed" 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 (v.)

"to kill," 1930, from off (adv.). Earlier verbal senses were "to defer" (1640s), "to move off" (1882). Related: Offed.

updated on October 14, 2021

Definitions of off from WordNet
off (adj.)
not in operation or operational;
the oven is off
the lights are off
off (adj.)
below a satisfactory level;
his performance was off
an off year for tennis
off (adj.)
(of events) no longer planned or scheduled;
the wedding is definitely off
Synonyms: cancelled
off (adj.)
not performing or scheduled for duties;
He's off every Tuesday
off (adj.)
in an unpalatable state;
Synonyms: sour / turned
off (adv.)
from a particular thing or place or position (`forth' is obsolete);
went off to school
they drove off
Synonyms: away / forth
off (adv.)
at a distance in space or time;
the boat was 5 miles off (or away)
the party is still 2 weeks off (or away)
Synonyms: away
off (adv.)
no longer on or in contact or attached;
he shaved off his mustache
clean off the dirt
off (v.)
kill intentionally and with premeditation;
Synonyms: murder / slay / hit / dispatch / bump off / polish off / remove
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