Green’s Dictionary of Slang

1. cocaine, usu. of high quality.

1971		R. Woodley Dealer 1: He snorted two spoonfuls in each nostril—a two-and-two [...] ‘That,’ he said [...] ‘is top-shelf coke, superfly’.
1974		Eble Campus Sl. Mar. 6: superfly – cocaine [...] also described as a super spanish fly.
1991		D. Jenkins You Gotta Play Hurt 269: There must have been two hundred entrepreneurs milling about [...] each one wearing a gold pendant on which his name was engraved. Among the names I read on pendants: Deion, [...] Corinne, Louie, Pony, Roof Top, Bernice, Superfly.
1997		N. Barlay Curvy Lovebox 167: What is happening in Stonebridge? Killah babes? Slip and slide? Supahfly?

2. (US) an ostentatious pimp.

1991

B. McCarthy Vice Cop 138: Within seconds, the door opened, the pimp emerged, a massive black Super Fly in a purple felony hat, wearing a long fur coat and two stunning women on each arm.