Green’s Dictionary of Slang

1. a drink, an act of drinking.

1963–74		B. Humphries Barry McKenzie [comic strip] in Complete Barry McKenzie (1988) 22: I’ll hop out for a swift chuckle to make room for the last couple of chug-a-lugs.
1974		N. Heard Cold Fire Burning 79: The wine was on the table; I grabbed it and turned it up, taking large, greedy chugs.
1983		J. Byrell (con. 1959) Up the Cross 19: Bruce the Rooster proposed a chugalug.
1988		McGill Dict. of Kiwi Sl. 28/2: chugalug act of drinking, usually a beer, in one gulp, or a drinking bout; eg ‘Fancy a few chugs after work, Nobby?’.
2003		McGill Reed Dict. of N.Z. Sl. [as cit. 1988].
2007		N. McCall Them (2008) 13: Tyrone picked up a beer and took a chug.
2012		M. McBride Frank Sinatra in a Blender [ebook] I unscrewed the lid and knocked back a series of vigorous chugs.
2013		T. Black Ringer [ebook] n.p.: Nothing but stress, nothing a few chugs on a good bevy won’t sort.

2. attrib. use of sense 1.

1967		F.J. Hardy in Great Aus. Lover Stories 41: There were fifty entries for the Chugalug Championships.
1978		L. Kramer Faggots 347: He realized that he was watching the two rival journalists who were Bella and Blaze engaging in a chug-a-lug contest.