Green’s Dictionary of Slang

(US black) an instance of outwitting, insult or verbal humiliation.

1974

R.D. Abrahams ‘Black Talking on the Streets’ in Bauman & Sherzer Ethnography of Speaking 245: Cursing [. . .] may be either a device of playing, or used very seriously, as are mounting, charging, getting on someone’s case, and many others.