A gang was a group of associated individuals.
Jack Chance was the leader of Sabalom Glitz's gang of robbers. (PROSE: Mission: Impractical)
The Seventh Doctor was caught in a gang war's crossfire in San Francisco on 30 December 1999. This lead to him regenerating into his eighth incarnation. (TV: Doctor Who)
Basil Bailey was the leader of a gang at Coal Hill School that dealt in illicit drugs. (PROSE: The Eight Doctors)
Sunset Strip, a market visited frequently by gang members, was most busy on Tuesdays. (COMIC: Gangster's Paradise)