asking "what's up?" or "what's going on?" sometimes used when someone is mad also.
Joe: what u on bro?
Alex: just chillin dawg, u already know!

Alex: Joe, how u gon' get on my girl like that? what u on??
Joe: That hoe was askin for it folk.
by Joe Weezy April 30, 2006
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Idiot expression used by those with low intellectual capacity. An alternative to asking "What are you doing". Not to be confused with WHATTAYADOIN or WHAT THE HELL ARE YOU DOING?!?!
Via AIM...

Teabag934: What u doin?
Dough 1583: Entering stage 4 of robotic development mode.
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One of the most unintelligent things a person could say and get rich off of. Way to go Lil' Jon.
by Jake Sutliff October 26, 2006
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what u talkin about?
"chanel told me she saw u n some ho at the game friday..that true?"

"man yo u know chanel dont like my ass she's had it in for me since day one..so what rap u spittin?"

by crazy lady 5 February 8, 2008
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what are u doing step bro is something that a step sister says when she gets stuck in a provocative position and her STEP-BRO walks in with his big Ding Dong Shling Shlong and sticks it in his step sister and the iconic line is said WHAT ARE YOU DOING STEP BRO
Stepsis: oh no im stuck in the washing machine
Stepbro: Walks in with dick out and sticks it in his step sister
Stepsis: what are u doing step bro, did u at least use a condom?
Stepbro: Its fine were not related by blood so there's no chance of deformity
by Big ol Horse Ding Dong February 21, 2022
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