gangism

noun

1. (uncountable)The criminal or antisocial behaviour of gangs.

   “[…] our Western culture will certainly be in for individuation in its worst forms — political gangism, racketeering gangism, banker-broker gangism, rebate subterfuge, ruthlessly untruthful advertising, […]”

   “Everything about these youths seemed to indicate gangism. In interviewing one of the women's other children who was younger than the particular son who had come it at a later time, I asked if the brother had any gang affiliation.”