It is a back flip off a wall that was primarily used by a cornerd African American in the days of slavery to gain a better position against its pursuer. If done correctly, the person being subjected to the black flip will go momentarily unconcious giving the user an oppurtunity to escape. To this day the reason for the momentary unconciousness is unexplained but most believe it is due to the sheer amount of awesomeness that results from one.
Did you get that guy who was running down that alley?
No man, i had him cornered but then he pulled off a black flip on me
O shit, are you okay
Yea I'm alright just a bit dizzy, but man it was fucking awesome!