hoist by one's own petard

Meanings:

• 1.

  Early Modern Englishliteralarchaicliterary
  • To be blown up or physically lifted by one's own explosive device (petard).

• 2.

  WorldwideEnglish-speaking countriesidiomaticformalliterary
  • To suffer harm, defeat, or embarrassment as a direct result of one's own plan, plot, or action intended to harm others.