Back-fire

, v. i. 1. (Engin.) To have or experience a back fire or back fires; -- said of an internal-combustion engine. [ Webster 1913 Suppl. ]

2. 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. -- Back"-fir`ing, n. [Webster 1913 Suppl.]

. 1. 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. ]

2. (a) 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. (b) an explosion in the exhaust passages of an internal combustion engine. [ Webster 1913 Suppl. +PJC ]