half-man, n. — Green’s Dictionary of Slang

half-man n.

also half-a-man

[Scot. halfman, half a bottle of spirits; note man n. (6)]

(US black) a half-bottle of spirits, esp. whisky.

1939		AS 14.90: Half man [...] A half pint of whiskey. ‘A half man laid him out.’.
1988		(con. 1940) C.E. Lincoln The Avenue, Clayton City (1996) 48: On weekdays most people just wanted half-a-man to get them through the day.