1) a tactical retreat to keep your ass from getting the beatdown.

2) to run away like your muthafuckin' life depends on it.

3) to get lost, or to cowardly run away like punk ass you are
Example #1:

After a foolish hike through the Brooklyn Navy Yard, Caesar gets jumped by two thugish entrepreneurs and they seize his IPod and MAC laptop. After being thrown to the ground like a rag doll, the conversation goes something like this...

Entrepreneur Thug #1: Yo son it's payday up da fuckin' Zoo.
Entrepreneur Thug #2: Dats what im talking about.
A disoriented Ceasar tries to regain his composure.
Entrepreneur Thug #1: (looking at Ceasar) you still here, bitch ass nigga!
Entrepreneur Thug #2: Yo, you better run dat shit!
Ceasar flees never looking back.

Example#2

I gots robbed by a stick-up kid, he took my ice and bling, and told me to run dat shit. I was shittin' bricks so I ran like a lil' girl who gots her bike stolen from her.

Example #3
I had too many drinks and the enormous bouncer through me out of the club. He said, you better run dat shit, lil man! I screamed "yo mommas so fat..." but i ran away, like a punk ass, before the bouncer caught up to me.
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