A gathering of individuals who share a fundamentally flawed, factually incorrect or misunderstood notion who, by the act of communication and commiseration, grow more fervent in their belief and radical in behavior.

In other words: morons who get together and grow progressively dumber as as a group.
"Did you see that tax day tea party circlederp in the town square last night?"

"If our team wins the Super Bowl, how do we organize a celebration that doesn't turn into a late-night window-smashing car-flipping circlederp?"
by neuracnu April 15, 2009
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