backfire

noun

1. 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 the wrong direction.
2. An explosion in the exhaust passages of an internal combustion engine.

   “As much of Seattle tries to sleep, the Hellcat supercar goes on the prowl, the howls of its engine and the explosive backfires from its tailpipes echoing off the high-rise towers downtown.”

3. An explosion in other equipment.

   “The chief causes of rectifier backfiring in the Glasgow units were overheating or unfavourable anode/cathode temperature differential; it has proved possible to overcome these, although occasional backfires do still occur.”

4. (alt-of, alternative)Alternative form of back fire.

verb

1. (intransitive)Of a gun, cannon, Bunsen burner, etc., to fire in the opposite direction, for example due to an obstruction in the barrel.
2. (intransitive)Of a reciprocating engine, to experience a premature ignition of fuel or an ignition of exhaust gases, making a popping sound.

   “It was just after the Biafran war, and all the local people were still jumpy. Any time a car backfired or a police siren howled, they would dive under desks or tables instinctively.”

3. (idiomatic, transitive)To fail in a manner that brings down further misfortune.

   “His attempt to make money by importing luxury cars backfired horribly when fuel prices tripled.”

   “Her plan backfired on her.”

   “Obsessed only with cost, 'Sir Humphrey' saw that Transport for London 'got away' with ticket office closures on the Tube with only minor public pushback and miscalculated that it could do the same on the national network. This assumption backfired spectacularly.”

4. To set a back fire (small, controlled fire to limit spread of a larger fire).