When you slap someone at the back of their neck it is called a neckback.

slap
LOL, you just got one duty neckback!
by LiverThanThem July 17, 2008
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a person with a fat sack back pack on their neck piece resulting in a neckback
upper back fat
you'll know when u seee one
by Plidat November 13, 2003
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