petard: Meaning and Definition of

pe•tard

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. (cap.) Also calleda British spigot mortar of World War II that fired a 40-pound (18 kg) finned bomb, designed to destroy pillboxes and other concrete obstacles.
4. hurt, ruined, or destroyed by the very device or plot one had intended for another.