petard

 
Pronunciation: /pɪˈtɑːd/

noun

historical
  • a small bomb made of a metal or wooden box filled with powder, used to blast down a door or to make a hole in a wall.
  • a kind of firework that explodes with a sharp report.

Phrases

be hoist with (or by) one's own petard

have one’s plans to cause trouble for others backfire on one.
[from Shakespeare's Hamlet ( iii. iv. 207); hoist is in the sense 'lifted and removed', past participle of dialect hoise (see hoist)]

Origin:

mid 16th century: from French pétard, from péter 'break wind'