be hoist/hoisted by/with your own petard

hoist by/with (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. (Note: "hoist" in this instance is the simple past-tense of the archaic form of the verb, "hoise.") 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.See also: by, hoist, own, petard

be hoist/hoisted by/with your own peˈtard

(British English) be caught in the trap that you were preparing for another personThis is from Shakespeare’s play Hamlet. A petard was a small bomb.See also: by, hoist, own, petard