Slum Share definition Flag A person who hangs around a lower social level than one's own for the purpose of drugs, free loaderOr A classy person hanging around drug dealers for a free fix Man what happen to that girl we went to school with? She use to be hott and classy now she's a slum!I remember that guy from school, he played ball and everything now he has turned into a slum! Slum by ashane July 10, 2017 Get the Slum mug.