definition of
backfire

[1] #1 backfire n. [blowback] the backward escape of gases and unburned gunpowder after a gun is fired. wn

[2] #2 backfire v. [backlash, recoil] come back to the originator of an action with an undesired effect; "Your comments may backfire and cause you a lot of trouble". wn

[3] #3 backfire n. a loud noise made by the explosion of fuel in the manifold or exhaust of an internal combustion engine. wn

[4] #4 backfire v. emit a loud noise as a result of undergoing a backfire; "My old car backfires all the time". wn

[5] #5 backfire n. a fire that is set intentionally in order to slow an approaching forest fire or grassfire by clearing a burned area in its path. wn