A poo knuckler is someone that shoves there fist up another persons ass.
Guy 1: You poo knuckler
Guy 2: Do you even know what that means?
Guy 1: no, what?
Guy 2: a poo knuckler is when someone shoves a fist up your butt!
Guy 1: No way, you just pulled that definition out of your ass
Guy 2: Literly!
by Walruses unite February 1, 2011
Get the Poo Knuckler mug.