An original gangster. The OG is the elder and advisor of the current generation gangsters. Also used to describe David Robinson, the true OG of the Waterbury Mesivta.
Hot damn, look at OG Dave, He the realest nigga on the block.
OR
2: the old heads/ the niggas that was in the set for a long time. The " original gangsta"
If y'all use it wrong you gonna look stupid stupid
1:
"where you at La'Quence?"
"I'm at my OG crib slide."
2: "who that big nigga with the blick?"
"That's the OG big worm, he just got out the county he having a party at his OG's(his grandparents) crib tomorrow"