Green’s Dictionary of Slang

(orig. US black) pertaining to the lifestyle of a teen gang member.

1990		S. Morgan Homeboy 17: They wore full gangbang gear: designer jogging suits, unlaced Reebok hightops, baseball caps fixed askew over clear plastic shower caps, and sunglasses blacker than their skin.
1999		Guardian G2 1 July 21: Bring The Pain HBO special took heat for razzing on the idiocies of gangbanger culture.