Green’s Dictionary of Slang

(US black) mass.

1982

G. Tate ‘Beyond the Zone of the Zero Funkativity’ in Flyboy in the Buttermilk (1992) 41: A masterpiece of mindless pleasure made for both mass-ass and Maggot consumption. [Ibid.] 42: This old funk for new [...] is George’s way of begging his maker for reincarnation into mass-ass appeal.