Green’s Dictionary of Slang

tonic n.2

1. (a glass of) alcohol.

[US]Nat. Police Gaz. (NY) 4 Nov. 2/4: ‘This morning I got up jess about day to get me a tonic at de saloon’.
[Aus]Townsville Daily Bulletin (Qld) 1 Mar. 10/4: Breastin’ the bar to put the kind word on the publican for a farewell tonic.
[Aus]F. Berkery East Goes West 69: It also used to be the delightful practice of some of the ‘dags’ to journey on this train to Augusta to arrange for supplies of tonic, and to have a blow-out [...] No liquor was allowed on any of the trains. . but the harder they tried to enforce the rule, the more the grog came in [AND].

2. (Scot. teen) Buckfast Tonic Wine, a caffeinated fortified wine; orig. produced by monks in Buckfast Abbey, Devon, recently associated with ned n.4 (1) in Scotland, esp.the ‘Buckie Triangle’ – an area east of Glasgow between Airdrie, Coatbridge and Cumbernauld.

[Scot]G. Armstrong Young Team 10: We [...] pass a bottle ae Tonic aboot that we aw chipped in fur.

In derivatives

tonicked (adj.)

(Aus.) drunk.

[Aus]Truth (Sydney) 14 Apr. 3/5: He comes home tonicked, but not too tonicked.
[Aus]W.A. Sun. Times (Perth) 21 Apr. 1/1: One tonicked toaster attributed the beauty of the Swan scenery to the monied Mayor.
[Aus]Bulletin (Sydney) 16 July 14/2: We had a pig raffle at Gohanner Flat t’other night, an’ wos real jolly, we wos. In course we wos all a bit tonicked.
[Aus]Bulletin (Sydney) 1 Feb. 13/1: When ’twas seen That his team was tonicked only to the verge of talking fight, Not a sober man would back him for a bean.
[Aus]Sun. Times (Perth) 24 Dec. 2s/3: They talked the ladies seasick and the bone-fides blue, / Till all on board got tonicked up.
F. Leechman Opal Bk 57: The wicked old lout had been ‘tonic’d’ as they call it and had wandered about bushed for twentyfour hours.