Green’s Dictionary of Slang

Mercedes n.

[the car of the same name and status]

(US black) an elegant woman with good looks and an attractive figure.

[US]E. Folb Runnin’ Down Some Lines 142: Women dey like a Porsche, a Mercedes or a Cad: [...] Mercedes is not too big an’ not too small. Jus’ fine to look at and bad to ride.