Petard

[pi-tahrd] /pɪˈtɑrd/

noun
1.
an explosive device formerly used in warfare to blow in a door or gate, form a breach in a wall, etc.
2.
a kind of firecracker.
3.
(initial capital letter). Also called Flying Dustbin. a British spigot mortar of World War II that fired a 40-pound (18 kg) finned bomb, designed to destroy pillboxes and other concrete obstacles.
Idioms
4.
hoist by / with one’s own petard, hurt, ruined, or destroyed by the very device or plot one had intended for another.
/pɪˈtɑːd/
noun
1.
(formerly) a device containing explosives used to breach a wall, doors, etc
2.
hoist with one’s own petard, being the victim of one’s own schemes
3.
a type of explosive firework
n.

1590s, “small bomb used to blow in doors and breach walls,” from French pétard (late 16c.), from Middle French péter “break wind,” from Old French pet “a fart,” from Latin peditum, noun use of neuter past participle of pedere “to break wind,” from PIE root *pezd- “to fart” (see feisty). Surviving in phrase hoist with one’s own petard (or some variant) “blown up with one’s own bomb,” which is ultimately from Shakespeare (1605):

For tis the sport to haue the enginer Hoist with his owne petar (“Hamlet” III.iv.207).

See hoist.