For blacks, omg was officially ruled for whites. whenever a black person would use "omg" they would instead use "osn" which means "Oh Shit nigga!".
White person example:
Guy 1: Hey did you do biology homework?
Guy 2: Omg i totally forgot about that.

Black people
Guy 1: Ay did you do biology?
Guy 2: Osn, i forgot all about that.
by DatNigga4rmOuterspace May 25, 2009
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OOOh SHIT NIGGAAA

Started By The Basketball and Track team of UC
Kid1: Osn Did u see rayray he just ran a 16.1 in 110 hurdles.

Kid2: Osn He fast as fuck for his first year
by Mmmmmmmmm18 June 03, 2009
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means "Oh shit nigga". meant for black people who think "OMG" is to white.
by jakemebabe101 May 25, 2009
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A black version of OMG
stands for: Oh Shit Nigga
Devin: Damn, that girl is a double D!

Zavier: Osn! Foreals?!
by Hagigamafuh May 25, 2009
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"Oh shit nigga!"

A Black version of "OMG", which IS too white of a term to use for Blacks.

An acronym not meant to be used by anyone who isn't Black.
OSN! I lost my "Chris Rock: Bigger & Blacker" DVD!
by Oh man. o3o September 18, 2009
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