A figurative slap in the form of a harsh, verbal put down, usually a superior (or someone who thinks they are) to a subordinate to show who is the pimp and who is the 'ho.
Dude 1: The boss gave you a real pimp slap this morning when you suggested flex time.
Dude 2: I know, in front of everyone. When she hasn’t been laid in a while, watch out, she will pimp slap you everytime.
Playa 1: Did you see that hottie eyeballing me at the club last night.
Playa 2: Please, that hood rat was mad dogging you because she can’t believe anyone is still wearing Tommy is 2006.
Play 1: Why you pimp slap me like that, I thought we were brothers?