noun
petard
puh-TARD/pəˈtɑːrd/
A small explosive device formerly used to breach gates or walls.
The petard rests against the fortress gate with its short fuse sparking.

Etymology
The verb meaning “break wind” underlies the name of this small bomb. A weapon used to blow open gates thus has an unexpectedly earthy connection to bodily gas.
In context
Hoist with his own petard: and 't shall go hard
More examples
- The soldiers fastened a petard to the heavy wooden door.
- Petards helped besieging armies breach fortified entrances.
- His attempt to frame her backfires, leaving him hoist with his own petard.
Forms
petard · petards