Green’s Dictionary of Slang

gin, or a particular quality of gin.

1817		‘Elegy Writen in Spa-Fields‘ in Morn. Post 13 Feb. 2/4: Full many a glass of DEADY'S gin so bright, The week unsteady hands of topers drop.
1819		‘One of the Fancy’ Tom Crib’s Memorial to Congress 35: As we’d been summon’d thus to quaff / Our Deady o’er some State Affairs [...] Deady’s gin, otherwise, Deady’s brilliant stark naked.
1820		‘Peter Corcoran’ ‘King Tims the First’ in Fancy 26: Give us a keg, we’ll pull a little Deady.
1821		Egan Life in London (1869) 57: The majority of John Bull’s descendants [...] prefer the fumes of porter, and the strong smell of Deady’s Fluid.
1823		Devizes & Wilts. Gaz. 29 May 2/4: ‘Lushing’ was the word, and the ‘heavy wet’ and ‘Deady’s elixir’ evaporated tike dew before the sun.
1824		J. Wight Mornings in Bow St. 44: [T]he bearer of it [i.e. a funeral torch] took a little of Deady’s consolatory on his way back from the mournful ceremonies.
1834		Southey Doctor 344/2: Some of the Whole-hoggery in the House of Commons he would designate by Deady, or Wet and Heavy, some by weak tea, others by Blue-Ruin, Old Tom.
1836		Comic Almanack Apr. 52: A [...] man, suddenly fell down in one of the gin-palaces in St. Giles’s; after having, it was supposed, put an end to his existence, by swallowing a quartern of Deady’s Best.
1843		W.T. Moncrieff Scamps of London I i: [as a nickname] Old Deady, the savage, can be dangerous enough at times.
1870		London City Press 9 July 5/1: Theyprefer a squeeze amidst clouds of tobacco, porter fumes, and the smell of Deady’s fluid at a free-and-easy club.
1871–82		B.M. Carew Life and Adventures.
1890		C. Hindley Vocab. and Gloss. in True Hist. of Tom and Jerry 171: Deadly’s Fluid. Gin, distilled at Deady and Hanley’s, Hampstead Road.
1911		J. Masefield Everlasting Mercy 11: Faces of men who’d never been / Merry or true or live or clean; [...] Nor took a punch nor given a swing, / But just soaked deady round the ring.