It's meant to make somebody feel like a bitch if it works.
The guy was talking about bitchslapping a guy instead of hitting with a closed fist, saying the other guy was a bitch. Well, when he wanted to hit with closed fists, that was always an option, so was slapping each other around like bitches, and calling it a bitchslap, or anything else. It really all depended on how much more badass than the other guy he felt, if he felt like fighting in the first place.
Person 1: "Gimme 500 or Imma bitchslap yo face!"
Person 2: "Aw hell nah wheezy outta here"
A term meaning "I will slap the shit out of you so you better shut your ass up"
The impulsive action caused when a moron needs a good back hand or to but because of the harp program doing it's thing it causes said person the "slapee"to fly into the upper atmosphere and be in limbo forever also known as the bitchslapation zone...
I will knock Heather to bitchslapation if shelooks at me cross-eyed one more time