Definitions:

1. to come back to the originator of an action with an undesired effect verb
   • Your comments may backfire and cause you a lot of trouble.
2. to emit a loud noise as a result of undergoing a backfire verb
   • My old car backfires all the time.
3. to set a controlled fire to halt an advancing forest to prairie fire verb
   • We had to backfire to save the land.

Synonyms:

• backlash
• blowback
• boomerang
• recoil