be hoist by (one's) own petard(redirected from be hoist by their own petard)
be hoist by (one's) own petard
To be injured, ruined, or defeated by one's own action, device, or plot that was intended to harm another; to have fallen victim to one's own trap or schemes. ("Hoist" in this instance is the past participle of the archaic verb "hoise," meaning to be raised or lifted up. A "petard" was a bell-shaped explosive used to breach walls, doors, and so on.) I tried to get my boss fired by planting drugs on him, but I was hoist by my own petard when the police caught me with them beforehand. The senator continually called on authorities to investigate her political opponent's alleged tax evasion. Now it seems as though she may have been hoist by her own petard, as federal agents indicted her for tax fraud on Monday.
Farlex Dictionary of Idioms. © 2022 Farlex, Inc, all rights reserved.