Jerking off and then licking your hand clean of the lubricant and seminal fluids.
Dang, Johnny is a sick puppy, I caught him nanning after he jerked off!
by manly manning November 18, 2013
Similar to the more widely renound sexual practice of Dogging, Nanning is cropping up heavily around the industrial estates of North East London. Men flood to predefined meeting points in their vehicles, with their Nan's riding shotgun. The Nan's are then paraded amid the circle of parked cars, before being traded amongst the other men or 'Nanners'. The swapped Nan's are then sexually gratified on the car bonnets.
Hey Norris, do you fancy a spot of Nanning this evening?
by Tony Clifton May 11, 2006