set off

present singular third person sets off · participle present setting off

1. idiomaticintransitiveTo leave; to set out; to begin a journey or trip.

   He set off in search of better opportunities.

   2 more examples

   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

   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

   Synonyms: set forth, take off, 23 skidoo, beat it, bug off, remove, egress, bugger off

2. idiomatictransitiveTo begin; to cause; to initiate.

   I had no idea that one simple comment would set off such a huge argument.

   Synonyms: bring forth, produce, bring forth, cause, contrive, create, ferment, forge

3. transitiveTo cause to begin.

   When he started giggling, it set us all off too.

4. idiomatictransitiveTo cause to explode, let off.

   What a tragedy, that someone would set off a bomb in a crowded place.

   1 more example

   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

   Synonyms: blow up, detonate, touch off

5. idiomatictransitiveTo put into an angry mood; to start (a person) ranting or sulking, etc.

   Don't set him off or he won't shut up all day.

   Synonyms: incense, put out, affront, aggravate, anger, antagonize, awrath, burn up

6. idiomatictransitiveTo enhance by emphasizing differences.

   Her plain white dress was set off by a bright red stole.

   1 more example

   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

7. idiomatictransitiveTo 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.

   1 more example

   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

   Synonyms: counter, counteract, negate, offstand

8. historicalmediaTo 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.