Definitions
1.nounA small, controlled fire set in the path of a larger uncontrolled fire, in order to limit the spread of the large fire by removing its fuel.
2.nounAn explosion produced either by a running internal combustion engine that occurs in the air intake or exhaust system rather than inside the combustion chamber or unburned fuel or hydrocarbons ignited somewhere in the exhaust system.
3.nounA premature explosion in the cylinder of a gas or oil engine during the exhaust or the compression stroke, tending to drive the piston in the wrong direction.
4.nounAn explosion in the exhaust passages of an internal combustion engine.
5.verb(of a gun, cannon, Bunsen burner, etc.) To fire in the opposite direction, for example due to an obstruction in the barrel.
6.verb(of an engine) To experience a premature ignition of fuel or an ignition of exhaust gases, making a popping sound.
7.verbTo fail in a manner that brings down further misfortune."His attempt to make money by importing luxury cars backfired horribly when fuel prices tripled."