a device contrived to hurt another person; boobytrap; an explosive contraption used in warfare to blow in a door or form a breach in a wall.
to "hoist by one's own petard" means you have been hurt or caught by the very device that you intended to hurt someone else. This phrase is often used mockingly, as if to say that you stepped in your own mess.
by Dr. Dave January 8, 2004
Medieval demolition. Set down by people, and then the person runs. In many cases, the person may fail to run, therefore they have been "blown away by their own petard", which is also a common saying.
Petard is nothing to do with retard. You are retarded, not petarded. :P
by Steaver370 July 30, 2004
somebody named peter that is retarded or acts like it
peter stop being a petard and quit lighting my hair on fire!
by esse March 23, 2005
A combination between a penis and a retard.
That kid with the big head is such a petard.
by Steven September 16, 2003
This is what causes males (typically 13-19) to draw dicks whenever they get the chance to.
You know those dicks drawn in sharpie in the public bathroom? Well thats just another petard.
by ROFL-CAKE December 2, 2010
A portmanteauof "retarded" and "petard," it describes a plan backfiring on you in such a way that you are left looking utterly ridiculous. It combines the concept of retarded--which is to say mentally deficient--and the phrase "hoisted by your own petard," which means to have damage done to you by the means you had intended to employ to damage others. A petard is an explosive used to break down barricades in warfare, and so petarded can also mean "blown up," in some circumstances.
You ratted Dan out for stealing that camera, but in doing so proved that you were his accomplice? Dude, you're petarded.

Jim just petarded the front door trying to take out his ex, but the door blew up and a shard of it went through his windshield. Totally petarded.
by Talmanes December 2, 2006