Green’s Dictionary of Slang

1. (Aus./S.Afr.) counterfeit, spurious, fake; thus (mining jargon) schlenter, a fake diamond sold as the real thing.

1886		Sporting Times 10 Apr. 3/2: I hates all the shlenter tokkefum, / As togs up and tries to look goy.
1888		Melbourne Punch 2 Feb. 11/2: The P.R. has fallen rather low in public estimation since the schlenter fight between King and Heenan.
1891		Bird o’ Freedom (Sydney) 4 Apr. 6/1: I know thee to be cute fellows, oh, my people, when thou art laying the odds on a racecourse, or [...] a ‘schlinter’ rowing match.
1895		Bulletin (Sydney) 5 Jan. 3/2: The long-beerians, rabbiters, spielers, fat-heads, slanter-bookies, etc., were all there.
1900–10		Stephens & O’Brien Materials for a Dict. of Aus. Sl. [unpub. ms.] 147: SCHLENTER: crooked, faked. In Australia first applied to pugilistic encounters in which the winning and losing was prearranged. Now applied to any competing or contest which is a swindle or not bona-fide.
1900		Truth (Sydney) 15 July 8/2: Every kind of slenter game / [...] / Sum of witch I dossent name.
1901		Sydney Sportsman (Surry Hills, NSW) 4 Sept. 1/5: There were then no schleinter bookies, / Who when losing brought the scales / To adjust the punter’s pewter.
1904		Sun. Times (Perth) 20 Mar. 1/1: A long-ago mock marriage in a swagger Perth hotel has now had a scandalous sequel [...] on waking up from the wassail after the schlenter coupling the decayed financier swore to marry his cook.
1911		Truth (Perth) 14 Jan. 8/8: Where the business it are proper— / Not no low down slenter show.
1913		C. Pettman Africanderisms.
1918		L.J. Villiers Changing Year 14: ’Ooever put the cow outer my name Is square dink fer a cert ter stop a clout. Them shlanter goes gi’ me the pip straight out [AND].
c.1919		W. Lawless Darcy Story 26: If he was attempting any schlenter work would it not have been detected [AND].
1933		Bulletin (Sydney) 6 Sept. 40/3: ‘[H]e ain’t been taught any schlenter tricks’.
1966		Ramson & Wilkes Aus. Eng. 188/2: [Index] slanter, schlenter, slenter, slinter, 160, 161 .

2. (Aus.) used of an individual: dubious, untrustworthy, ‘up to no good’.

1904

Sydney Sportsman (Surry Hills, NSW) 21 Dec. 2/7: I could see as he were slenter / With the crook of ½ an eye.