lady snow, n.² — Green’s Dictionary of Slang

lady snow n.²

[SE lady + snow n.¹ (2a); note cocaine is a ‘feminine’ drug, see girl n.²]

(drugs) cocaine.

1967		P. Thomas Down These Mean Streets (1970) 258: That’s my woman, Lady Snow. [...] I sure wish I could cop some.
1969		R.R. Lingeman Drugs from A to Z (1970).