ˈbækˌlæʃ ˈbuːməɹæŋ ˈbuməɹæŋ ɹɪˈkɔɪl a miscalculation that recoils on its maker set a controlled fire to halt an advancing forest to prairie fire emit a loud noise as a result of undergoing a backfire My old car backfires all the time come back to the originator of an action with an undesired effect Your comments may backfire and cause you a lot of trouble the political movie backlashed on the Democrats a fire that is set intentionally in order to slow an approaching forest fire or grassfire by clearing a burned area in its path a loud noise made by the explosion of fuel in the manifold or exhaust of an internal combustion engine the backward escape of gases and unburned gunpowder after a gun is fired