What is the meaning of backfire?

noun

• The backward escape of gases and unburned gunpowder after a gun is fired.
  • synonyms: blowback
• A loud noise made by the explosion of fuel in the manifold or exhaust of an internal combustion engine.
• A fire that is set intentionally in order to slow an approaching forest fire or grassfire by clearing a burned area in its path.
• A miscalculation that recoils on its maker.
  • synonyms: boomerang

verb

• Come back to the originator of an action with an undesired effect.
  • usage: "Your comments may backfire and cause you a lot of trouble"
  • synonyms: backlash, recoil
• Emit a loud noise as a result of undergoing a backfire.
  • usage: "My old car backfires all the time"
• Set a controlled fire to halt an advancing forest to prairie fire. .