Third-person singular simple present indicative form of backfire.
backfires when Sam decides to move out so Sarah can have her own room.
Unfortunately, this method often backfires, as an overly tired baby may not experience a peaceful slumber and in fact will probably awaken earlier than usual, cranky and still tired.
And to be honest, dating someone just because he/she is hot almost always backfires at some point.
People who drink are often depressed and seek an outlet to numb those negative feelings, but it backfires.
While staying awake may seem like the best way to achieve what they want in the waking hours, it actually backfires because of the devastating effects caused by the physiological responses to prolonged alertness.