When you have poo on your gooch.
When wiping your arse you accidently spread some shit onto your gooch, (this often happens when using a cheap brand of toilet paper) therefore you have poo on your gooch creating the word POOCH to describe this action. The gooch is the bit of skin between the ball sack and the anus.
by JuiceBoxspuddy July 12, 2009
The piece of skin between the scrotum and arsehole of a person who chooses to be a 'front-wiper'. Portmanteau of the two words 'poo' and 'gooch'. To be shouted at anyone discovered to be a front wiper at any available opurtunity...'POOOOOOOCH'
Mate, you're a front wiper? That smell must be your pooch then.
by Poochie boy March 13, 2008