Green’s Dictionary of Slang

1. a pawnbroker.

1859		Matsell Vocabulum.
1890–1904		Farmer & Henley Sl. and Its Analogues.

2. a swindling tipster.

1880		Sporting Gaz. (London) 30 Oct. 1108/3: [T]hat still more dangerous specimen of humanity known by the slang term of ‘lumberer,’ who invariably prey upon the young and unsuspecting.
1885		Bulletin (Sydney) 18 July 18/3: The temperance principles of the bully are as dear to him as the teetotal orator […]. A certain notorious English ‘welsher’ and ‘lumberer,’ known in police circles as Bill the Butcher, is a non-smoker and a sort of temperance apostle among his ruffianly friends.
1899		A. Binstead Gal’s Gossip 146: A bold, fearless narrative in song of the glories achieved by a squad of Her Majesty’s favourite regiment of Lumberers.
1904		Sydney Sportsman (Surry Hills, NSW) 9 Mar. 3/5: One of the lumberers undertook to act as his guide, philosopher, and friend and started to lumber him on to a double.
1946		S. Jackson An Indiscreet Guide to Soho 121: Petty ‘lumberers’ (con. men who do rapid kerbside deals like taking money for liquor from drunken victims and then disappearing.
1950		P. Hoskins No Hiding Place! 191/1: Lumberers. Kerbside confidence tricksters.
1999		G. Seal Lingo 146: As well there were other varieties of cheat including a lumberer, a tipster who swindles.

3. any form of swindler.

1881		Herald (Melbourne) 6 Aug. 2/7: [of card-sharps] They Say [...] A party of ‘lumberers’ [...] taking on a well-known Boniface who knew his way around.
1883		Sporting Gaz. (London) 8 Sept. 1097/2: Probably several of my readers have also been robbed, perhaps will even be done this very year by a class known in slang parlance as ‘lumberers,’ men who live well, dress smart, and especially frequent the Gaiety and Criterion restaurants.
1886		‘Doss Chiderdoss’ in Sporting Times 6 Mar. 1/4: Two Johnnies lose, / Two partners win; / Two lumb'rers take / Two piles of tin.
1890		divorce court report July in Ware (1909) 171/2: Mr Gill felt instinctively that there was something wrong with this man’s appearance; and when this man came, in cross-examination, to give an account of himself, it accorded with the well known expression ‘lumberer’.
1898		Binstead & Wells Pink ’Un and Pelican 126: ‘Pimples’, as the lumberer was called among his kind, was by no means a desirable security.
1910		‘Doss Chiderdoss’ ‘Poetry in Prosaic Places’ Sporting Times 19 Feb. 3/2: The most transparent lumberer in town who on him works / The old ‘Confidence’ manoeuvre, scoops the pool.

4. a prostitute or pimp who specializes in robbing her/his clients.

1900–10		Stephens & O’Brien Materials for a Dict. of Aus. Sl. [unpub. ms.] LUMBERER: A brothel tout, a man who decoys men down lanes or alleys or into bilking houses for purposes of robbery.
1941		Baker Popular Dict. Aus. Sl.
1966		Trimble 5000 Adult Sex Words and Phrases.

5. (Aus.) a traffic police officer (c.f. walloper n.¹ (8)).

1968

D. O’Grady A Bottle of Sandwiches 19: The lumberer got off his bike [...] faced our truck and surveyed the number plate.