The threat implied by children who knock on the doors on the 31st of October, widely known as Halloween, after saying the phrase "Trick or Treat".

The threat is ambiguous, and can result in many different outcomes. Egging, toilet-papering, or bags full of dog shit are commonly expected, but graffiti, and vandalism, and other criminal acts may be committed.
Police Officer #1: "Did they threaten you in any way, did you see weapons of any kind?"
Larry David: "No, there was no threat, except for the "trick" threat."
Police Officer #2:"What's the trick threat?"
Larry David: The "Trick or Treat". No treat; trick. It's a threat! How far can you take these tricks?"
Police Officer #1: "If it was any other night sir-"
Larry David: "TRICK OR TREAT -- BANG, BANG!"
by Bdent27 July 8, 2011
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