Abbreviation of Original Gangsta. First used by Ice T, with his 1991 album "O.G original gangster", and later adopted by gangsta rappers to refer to an old gangster.
The abbreviation of "original ganster", a term overused by SGs or studio gangsters and millions of people that have never done anything gangsterlike in their life. It no longer a means anything.
Alex:"can I get a discount, I'm a OG, nigga" Cashier: "you're about as OG as Drake ya yesmaster ass nigga, get the fuck out my shop hood rat" O.G.
1:look at that o.g aint no 1 cop shit from her
2:i heard she waz an o.g. cuz of her killin a wansta and took his whip to.
1:damn homie u bets ta not get in her wayz then
O.G. is an acronym standing for ORIGINAL GANGSTER. people and things can be described using O.G. as an adjective. it is almost always associated positivley.