"
Hoist with his own petard" is a phrase from a speech in
William Shakespeare's play
Hamlet that has become
proverbial. The phrase's meaning is that a bomb-maker is blown ("hoist", the past tense of "hoise") off the ground by his own bomb ("
petard"), and indicates an ironic reversal or poetic justice.
[1]
In modern vernacular usage of the idiom, the
preposition "with" is commonly exchanged for a different preposition, particularly "by" (i.e. "hoist
by his own petard") or "on", the implication being that the bomb has rolled back and the unfortunate bomb-maker has trodden on it by accident. The latter form is recognized by many
British and
American English dictionaries as an interchangeable alternative. Prepositions other than "by" and the original "with" are not widely accepted and may be seen as erroneous or even nonsensical in the correct context of the phrase.
