Started out of the Bed-Stuy, Brooklyn community and brought to the forefront by rapper Nine11Kevin aka Kevin Madison. A greeting like saying "Wassup" with the sound of the word "Boi" spelled B.A.I.I. meaning (Brooklyn Always In It) since Brooklyn is everywhere and pronounced like "Bye" or "Buy".
What Up Baii? I Aint Seen You In Mad Long baiiiii!

What Up Baii? Wus shakin wit da makin?

What Up Baii? Wassup Wit Da Wassup?

They Spelled It Bai... Betta Go & Get Dat I.. BAII*

Is Dat My Son? OH SHIT WHAT UP BAii!
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This term is used within a small, feminine, girl power oriented hip-hop community as a substitute for "what's up?" The term is solely used amongst openly feminine hip-hop musicians.
What up Baii? Haven't seen you in a bit.
by Tony Titt July 1, 2010
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