knocker, n.² — Green’s Dictionary of Slang

knocker n.²

[ety. unknown; ? link to Yid. naches, pleasure]

(Aus.) common sense.

1895–6		H. Lawson ‘Two Larrikins’ in Roderick (1972) 231: The old woman might have had the knocker to keep away from the lush while I was in quod.
1902		Bulletin (Sydney) 2 Aug. 16/4: In ’83 or ’84 13 men started overland from W.Q. with a few horses and very little capital but plenty of what they called ‘knocker.’ At every station they struck they demanded rations, and if police had been more plentiful in that part they would never have reached Kimberley.

off one’s knocker (adj.)

mad, insane, uncontrolled.

1894		Mirror of Life 28 July 3/3: ‘I didn’t threaten to shoot her. She’s balmy and off her knocker’.
1906		E. Dyson Fact’ry ’Ands 201: Fuzzy continued caperin’ [...] clean off his knocker, ’n’ pickled in misery.

put the knocker on (v.)

1. to hit hard.

1895

Mirror of Life 9 Nov. 14/3: In the fifth round Butler put the knocker well down on Ned Derrell’s jaw, which brought Ned to the boards.

2. (Aus.) to call a halt, to forbid.

2005

M.B. ‘Chopper’ Read Chopper 4 155: My old Dad put the knocker on it [i.e. a proposed assassination] with a passionate verbal tirade.