no obj.
1
- (of a vehicle or its engine) undergo a mistimed explosion in the cylinder or exhaust（车辆或其发动机）发生回火。
2
- (of a plan or action) rebound adversely on the originator; have the opposite effect to what was intended（计划, 行动）事与愿违; 产生反作用：
over-zealous publicity backfired on her.
过分热心的宣传反而对她产生了反作用。
1
- a mistimed explosion in the cylinder or exhaust of a vehicle or engine（车辆或发动机的）回火。
2
- N. Amer. a fire started deliberately to stop the progress of an approaching fire by creating a burned area in its path〈北美〉（为形成防火隔离带而有意点燃的）迎面火。