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1.
The sound caused by fat slapping against eachother when two fat people have sexual intercourse.
There was some serious fat slapping going on in the bunk next to me at fat camp.
by Ashleigh Bennett February 16, 2006
25 10
 
2.
The act of offering one's seat on public transport (most commonly the Subway) to a lady who appears to be pregnant but who is, as it turns out, just a bit fat.
John: Excuse me ma'am I see you are with child may I offer you my seat?

Natasha: What, bitch? Are you fat-slapping me!? I'm gonna beat yo' sorry ass!

John: Fuck off.
by J-Sox August 02, 2009
6 2
 
3.
some one who is fat and touches themselves at night.
my room-ate is a fatslap, all he does is eat and touch himself at night
by RVL12 March 04, 2008
3 0
 
4.
Vb. fat slapped, fat slap.ping
1. To strike the forehead of another with the flat plane made by the fingers as they are pressed outright and together making a loud, high pitched noise.

N. Fat Slap
1. The act of fat slapping
2. The sound made by such a blow
The boy fat slapped his friend, embarassing him greatly in front of the group.
by unbornchickenvoices January 09, 2006
4 4