Original gangster

O G means original gangsta
those tru gangstas from way back in the day that jacked ya and left nothing but you boxers and socks

o.g. : original gangsta

a retired gangster who sits on the porch in the ghetto and preaches to the youngsters.

original gangster. Being, or being related to the stereotypical 1970's gangster's lifestyle

Jay-Z's imaginary friend.

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)

Orangutan Ganja - Really strong weed that Asian Orangutans smoked with Budda. Now used as a marketing term universal adjective that has largely lost its original meaning. Used to describe strong weed (i.e., OG Kush, OG Sativa, OG Indica, etc.).