Green’s Dictionary of Slang

sophisticated lady n.

[play on girl n.2 (1) + the ‘smart’ image of the drug]

(US black) cocaine.

[US]E. Folb Runnin’ Down Some Lines 166: Say, fine young lady like yo’ self [...] you go fo’ d’ ‘sophisticated lady’ right? Like little coke get you tight, blow your mind and make you right!!