Green’s Dictionary of Slang

whiz n.5

[abbr.]

(US) whiskey.

[US]J. Thompson Savage Night (1991) 70: All I could smell was the whiz he’d been drinking.
[US]J. Thompson Texas by the Tail (1994) 161: He sent out for a couple of jugs of good booze [...] Teddy’s appetite for the whiz had increased with her years.