A term used when one has no facts or strong arguments to support some bull shit that he had said. Usually used when the user of the term is confident that the other person has no knowledge on the matter.
Bill: Did you know that the narwal is the only mammal to have a horn?

Joe: I think it's really a tooth.

Bill: YOU WANT TO BET?!?!?!
by ÆNK June 19, 2010
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