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1.
Slappage is the amount by which your balls urgently slap against the arse of the female you're banging.
example 1:
Stud thinking: "I need to give it more slappage, a lot more come on ya bitch get screamin"

example 2: man and wife in bed
Woman : "Oh for gods sake Derek give it some fuckin arsehole slappage will you, come on swing them bollocks like a pair of demolition balls"
by fahuck muhommad March 05, 2008