Thanks to Pearl McE.
Ed note about “petard” from AI: “A petard is a small, conical-shaped medieval bomb used to breach gates or walls by sappers, frequently prone to backfiring, which originated the phrase ‘hoist by your own petard’—meaning to be destroyed by one’s own trap. Originating in the 16th-century, the term comes from Middle French péter (to break wind), implying an explosive, ‘fart-like’ device.”
