If someone that looks to be a gang banger says it, it most likely means
"West Side Or Die."
Originated in Tupelo, Mississippi then moved to Wendell, North Carolina. Anywhere in between will be the followers of the tradition. It's recommended not to f*** with them, ever. Known for stealing, killing, and being thugs in general.
"WSOD round here homie."
"Oh shit, we gotta go bro, he's a thug, dip!"