A fire started ahead of a forest or prairie fire to burn only against the wind, so that when the two fires meet both must go out for lack of fuel. [Webster 1913 Suppl.]
A premature explosion in the cylinder of a gas or oil engine during the exhaust or the compression stroke, tending to drive the piston in a direction reverse to that in which it should travel; also called a knock or ping. [Webster 1913 Suppl.]

backfire, v. i.

To have or experience a back fire or back fires; -- said of an internal-combustion engine. [Webster 1913 Suppl.]
Of a Bunsen or similar air-fed burner, to light so that the flame proceeds from the internal gas jet instead of from the external jet of mixed gas and air. [Webster 1913 Suppl.]

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OXFORD DICTIONARY

backfire, v. & n.
--v.intr.
1 undergo a mistimed explosion in the cylinder or exhaust of an internal-combustion engine.
2 (of a plan etc.) rebound adversely on the originator; have the opposite effect to what was intended.
--n. an instance of backfiring.

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THESAURUS

backfire

backlash, backlashing, balefire, bang, beacon, beacon fire, blast, blaze, blow out, blow up, blowout, blowup, bonfire, boom, boomerang, bounce, bounce back, bound, bound back, burning ghat, burst, bust, campfire, cannon, cannon off, carom, cheerful fire, combustion, come to grief, comeback, conflagration, contrecoup, corposant, counterattack, counterblast, counterblow, counterfire, counterinsurgency, countermeasure, counterrevolution, counterstep, counterstroke, cozy fire, crackling fire, crematory, death fire, defense, detonate, detonation, discharge, explode, explosion, fall through, fen fire, fire, fizzle, flame, flare, flash, flashing point, flicker, flickering flame, fly back, forest fire, fox fire, fulguration, fulminate, fulmination, funeral pyre, go off, have repercussions, ignis fatuus, ignition, ingle, kick, kick back, kickback, lambent flame, lash back, lay an egg, let off, marshfire, miscarry, miss, open fire, prairie fire, pyre, raging fire, rebound, rebuff, recalcitrate, recalcitration, recoil, repercuss, repercussion, report, repulse, resile, resilience, retort, ricochet, sea of flames, set off, sheet of fire, shoot, signal beacon, smudge fire, snap back, spring, spring back, three-alarm fire, touch off, two-alarm fire, watch fire, wildfire, witch fire

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ROGET THESAURUS

backfire

Insulation

N insulation, fire extinction, insulation, incombustible material, noncombustible material, fire retardant, flame retardant, fire wall, fire door, incombustibility, incombustibleness, extincteur, fire annihilator, amianth, amianthus, earth-flax, mountain-flax, asbestos, fireman, fire fighter, fire eater, fire department, fire brigade, engine company, pumper, fire truck, hook and ladder, aerial ladder, bucket, fire hose, fire hydrant, backfire, firebreak, trench, aerial water bombardment, wet blanket, fire extinguisher, soda and acid extinguisher, dry chemical extinguisher, CO-two extinguisher, carbon tetrachloride, foam, sprinklers, automatic sprinkler system, fire bucket, sand bucket, fire alarm, evacuation alarm, fire code, fire regulations, fire, fire inspector, code violation, citation, incombustible, nonflammable, uninflammable, unflammable, fireproof, fight fire with fire.

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