Backfire means the premature ignition of fuel in a car.(verb)
A car making a loud explosive noise is an example of backfire.
Backfire is defined as something happens in the opposite way than you wanted it to happen.(verb)
An example of backfire is when you buy your wife roses to make her happy and she gets mad because you forgot that she hates roses.
The definition of backfire is a sound made by an engine because the fuel in it is not burning correctly.(noun)
A loud popping noise coming from the engine of a car is an example of a backfire.
See backfire in Webster's New World College Dictionary
See backfire in American Heritage Dictionary 4
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