It is a logical fallacy that can be identified as when someone says something so absolutely ridiculous and stupid you just want to slap them with your dick because they seriously believe the shit they're saying.
My Roommate: Seriously, if Flash ran into space fast enough he would take all of the air with him.

Me: It really doesn't work that way.

My Roommate: You're fucking stupid, how the fuck did you even get into college?

Me: That is a textbook no true douchebag fallacy *dick slap to the face*
by Bitch Puddin' February 14, 2012
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