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Synonyms

backfire

American  
[bak-fahyuhr] / ˈbækˌfaɪər /

verb (used without object)

backfired, backfiring

  1. (of an internal-combustion engine) to have a loud, premature explosion in the intake manifold.

  2. to bring a result opposite to that which was planned or expected.

    The plot backfired.
    Synonyms:
    bomb, flop, boomerang, miscarry

  3. to start a fire deliberately in order to check a forest or prairie fire by creating a barren area in advance of it.

noun

  1. (in an internal-combustion engine) premature ignition of fuel in the intake manifold.

  2. an explosion coming out of the breech of a firearm.

  3. a fire started intentionally to check the advance of a forest or prairie fire.

backfire British  
/ ˌbækˈfaɪə /

verb

  1. (of an internal-combustion engine) to emit a loud noise as a result of an explosion in the inlet manifold or exhaust system

  2. (of an endeavour, plan, etc) to have an unwanted effect on its perpetrator

    his plans backfired on him

  3. to start a controlled fire in order to halt an advancing forest or prairie fire by creating a barren area

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

noun

    1. an explosion of unburnt gases in the exhaust system

    2. a premature explosion in a cylinder or inlet manifold

  2. a controlled fire started to create a barren area that will halt an advancing forest or prairie fire

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Etymology

Origin of backfire

An Americanism dating back to 1775–85; back 2 + fire

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

The pressure is now on CEO Vinai Venkatesham - previously at Arsenal - sporting director Johan Lange, and the Lewis family, who are over-seeing affairs, as the gamble of Tudor's appointment continues to backfire.

From BBC • Mar. 24, 2026

But such a strategy could ultimately backfire, Marko Kolanovic, a former top strategist at J.P.

From MarketWatch • Mar. 23, 2026

This strategy "will backfire for specific audiences, particularly Westerners and others from democracies who are used to having freedom of expression," said Bohl.

From Barron's • Mar. 15, 2026

“Many presidents wouldn’t have that tone for personal moral reasons,” Rowland said, “but they also know that it can backfire when things don’t go well.”

From Los Angeles Times • Mar. 15, 2026

There was the loud bang of a backfire and the horseless chugged forward.

From "Dragonwings" by Laurence Yep

Definitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023

Idioms from The American Heritage® Idioms Dictionary copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.