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 01, 2006
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A nasty and insulting word for members of PETA, an animal-rights terrorist organization. They are usually destroying property or protesting at McDonalds.
An idiot PETArd threw paint on my fur coat, so I sued her for over a million dollars and won.
by weirdgirl June 18, 2003
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Derogatory term for one who belongs to PETA. See also terrorist.
Those PETArds are protesting outside the Outback Steakhouse again. Should I dump the T-bones on them, boss?
by SiliconHero April 25, 2003
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family guy's,peter,sufers from this illness.petarded is the name of one of the episodes where peter finds out he is retarded.(I won't tell u the rest,it'll ruin it for u)
you're so petarded.

stop being such a petard.
by Ching January 07, 2006
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When your clinically insane friend happens to be named Pete.
I took my friend Pete to the club, and he was thrown out for acting Petarded.
by Rubenderovr April 18, 2018
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puh-tard

1. Someone who has become borderline retarded because they smoked way too much Pot.
2. A dumb Pothead.
Cheech and Chong used to be funny back in the day. But now they're a couple of petards.
by DonnieLee August 14, 2006
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