the original gangsterz from the hood way back.
NOT GAME, 50 CENT OR G-UNIT.
OG is refering to the pioneers of gangster rap who were in it since the beginning such as Dr Dre, Ice Cube and the late Eazy-E (RIP)
"I stab it like a true no good nigga
should,I do it the way a down OG nigga would" - Eazy E; "still a nigga"