Green’s Dictionary of Slang

to hit someone, usu. with a club or cudgel.

1855		R. Lowe (Viscount Sherbrooke) ‘Songs of the Squatters’ Canto ii St. 7: When the white thieves had left me, the black thieves appeared, / My shepherds they waddied, my cattle they speared.
1863		Clarence & Richmond Examiner (Grafton, NSW) 13 Jan. 15/6: Note by Sambo [...] When dat fellar patter bait belongin’ to Sambo, Sambo been waddie dat fellar. Murry coolie Sambo.
1869		Victorian Hansard 18 Nov. IX 2310/2: They were tomahawking them, and waddying them, and breaking their backs.
1885		Bulletin (Sydney) 24 Jan. 6/2: Donald, it seems, was coming to Cairns, and on his way got an aboriginal to paddle him in his canoe up the river a distance, when the latter took a different view of the subject, waddyed him, and upset him in the water.
1895		‘Banjo’ Paterson ‘The Geebung Polo Club’ in Man from Snowy River (1902) 45: They waddied one another till the plain was strewn with dead.
1903		Bulletin (Sydney) 22 Oct. 35/4: He did ‘do it again,’ and, returning from town with his mate – both ‘tanked’ – was waddied to death by that individual.
1905		‘Song of the Squatter’ in ‘Banjo’ Paterson Old Bush Songs 104: My shepherds they waddied, my cattle they speared.
1941		Baker Popular Dict. Aus. Sl.