Green’s Dictionary of Slang

(US black) a drunkard.

[1857		Venus’ Miscellany (NY) 31 Jan. n.p.: Mr Lushington Camac, joking with his maid-servant [...] ‘Thy mistress, Mrs Lushy’ [etc]].
1944		D. Burley Orig. Hbk of Harlem Jive 143: Lushie—Drunkard.
1946		Mezzrow & Wolfe Really the Blues 94: The lushies didn’t even play good music.
1971		(con. 1930s) D. Wells Night People 53: Once upon a time, too, when lushies and junkies were fewer [...] rooms weren’t such a problem.