Top definition
When a person gets bored of one persons vagina so has to swap from fanny to fanny. Also if a person does not get action from his girlfriend or only once or twice a week so finds other girls so he can get gash all week.
Joe: Woww i've got a proper gash mash-up this week lillie on monday then ellie tuesday then my girlfriends sleeping over wednesday but friday i think i will see Georgie.

Jack: Ahh cant be arsed my girlfriends fanny is to tight i get bored might as well go fuck Georgie.
by sbvodka July 28, 2010
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