A slap to the back of the head whenever some has gotten a haircut.

The only downside to getting a haircut.
Josh: Joe’s got a fresh trim.
Jack: Yeah I know I gave him a barber slap earlier.
by *Write Pseudonym here* November 27, 2019
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A singular slap to the back of the neck when someone you know recently has a haircut within the past a day or two
Man, this haircut is awesome but I've been getting barber slaps all day
by Dreamon313 May 2, 2016
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