Idiomatic To leave; to set out; to begin a journey or trip.
He set off in search of better opportunities.
Considerable excitement was caused on the L.M.S.R. Aberdeen line out of Perth recently when a shunting engine in Perth North goods yard, whose driver and fireman were absent, was accidentally set in motion by a shunter and set off unattended on to the main line.1941 October, “Notes and News: A Highland Runaway”, in Railway Magazine, page 469:
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The train is booked to stop at Jiza for only three minutes, but more often than not twenty minutes or more are spent on shunting before it sets off again on what must be one of the most dreary journeys in the world.1956 March, R. C. Blaker, “The Hedjaz Railway”, in Railway Magazine, page 165:
What a tragedy, that someone would set off a bomb in a crowded place.
Wrex: There are acid tanks rigged up on that thing. Set them off. Millions of my ancestors died to put these things down. Don't let them come back.2008, BioWare, Mass Effect (Science Fiction), Redwood City: Electronic Arts, →ISBN, →OCLC, PC, scene: Secure Lab, Rift Station, Noveria:
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Idiomatic To put into an angry mood; to start (a person) ranting or sulking, etc.
Her plain white dress was set off by a bright red stole.
And then one afternoon in the hinder end of April came young Heriotside riding to the Skerburnfoot. His arm was healed, he had got him a fine new suit of green, and his horse was a mettle beast that well set off his figure.1902, John Buchan, The Outgoing of the Tide:
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Idiomatic To offset, to compensate for: to reduce the effect of, by having a contrary effect.
My taxes did not increase because the amount of my raise was set off by my losses in the stock market.
When a woman had made such a mistake, there was only one way to repair it,—to accept it. One folly was enough, especially it was to last for ever; a second one would not much set it off.1908, Henry James, chapter XXXIX, in The Portrait of a Lady (The Novels and Tales of Henry James), New York edition, volume (please specify |volume=I or II), Boston, Mass.; New York, N.Y.: Charles Scribner’s Sons, →OCLC; republished as The Portrait of a Lady (EBook #283), United States: Project Gutenberg, 1 September 2001:
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Media, Printing, PublishingHistorical To deface or soil the next sheet; said of the ink on a freshly printed sheet, when another sheet comes in contact with it before it has had time to dry.
Dated Something used to improve the appearance; a decoration, an ornament.
2
The act of setting off on a journey; a departure, a start.
3
Law A counterclaim; a distinct claim filed or set up by the defendant against the plaintiff's demand.
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Anything set off against another thing; a compensation, a counterbalancing circumstance.
D. Jerrold I do not contemplate such a heroine as a set-off to the many sins imputed to me as committed against woman.
[A]ll of them, of whatever age, require opportunities for rest and reading and indoor amusements, as a set-off against the constant strain on mind and body of looking after lunatics.1921, Montagu Lomax, The Experiences of an Asylum Doctor, London: Allen & Unwin, page 193:
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Business, Finance The situation where a bank or similar organisation repays itself money owed by an accountholder out of his or her account.