Green’s Dictionary of Slang

(Aus./N.Z.) used to denote something positive, or lit. or fig. substantial in size.

1898		N.Z. Times (Wellington) 14 May 3: The town was lively then, says Gett, doing a ‘bonser’ trade.
1898		Bulletin (Sydney) 18 June 20/1: [A]at the end of which time he ‘start[ed] a partner business with Mr. Chow Shum in Blenheim. In the year 1892 Blenheim was lively place, that time doing a bonsor trade.’.
1899		Cromwell Argus 1 July 5: Just listen while I sing about our Boncer Boys in Blue.
1901		Molong Exp. (NSW) 20 July 1/1: What they term ‘a bonser’ frost, turned up last Monday morning.
1901		Molong Argus (NSW) 26 July 2/6: Mr. Steve Grimson, late with Mr. Reschke, saddler, intends opening on his own account next week in the saddlery and harness line. I wish Steve every success. He is a ‘bonsor’ little chap.
1902		Lithgow Mercury (NSW) 11 July 4/5: Mr. T. Donnolly [...] , has promised a cup to the Lithgow Coursing Club for their next meeting. This [...] should be the means of enticing a ‘boncer’ entry.
1904		Eve. Star (Otago) 2 Jan. 5/3: [advert] Begin 1904 by Purchasing a ‘Bonsor’ Linoleum Polisher, latest labour-saving invention for housekeepers.
1904		Observer (Auckland) 4 Mar. 16: [T]hey spent £20 on what they would call a ‘boncer’ outfit of tent, rifles, ammunition, watches, blankets, pipes, and tobacco, and various things dear to the juvenile adventurer.
1906		Queenslander (Brisbane) 4 Aug. 32/2: [A]nd as we at that time had a ‘boncer’ cook – a real live French chef, in fact – he dished us up in good style.
1912		Hastings Standard 20 July 5: They thoroughly enjoyed the work and in their expressive way said it was ‘boncer’ change from the usual school routine.
1915		Observer (Auckland) 6 Nov. 4: ‘Boncer strikealight! My word! Where d’yer pinch it?’ The owner laughed. ‘I didn’t pinch it’.
1916		‘Anzac’ On the Anzac Trail 43: Our own O.C. was naturally anxious to make an A1 show in his particular line, so we prepared a boncer defensive position.
1916		Townsville Dly Bull. (Qld) 17 Mar. 6/5: [advert] LADIES’ SHAPES – This is a real ‘boncer’ line.
1918		Timaru Herald 11 Jan. 3: Adults pronounced it first-rate, while young people said it was ‘boncer’.
1920		K. Mansfield Bliss & Other Stories 45: The Trout boys had often spent the day with the Burnells in town, but now that they lived in this fine house and boncer garden they were inclined to be very friendly.
1927		Auckland Star 30 Sept. 6: ‘Come and see your present, Bill!’ said Dad, and he took him down to the shed. ‘Boncer double-furrow plough!’ crooned Dad.
1938		Auckland Star 13 Oct. 10: Asking him on the road home how he enjoyed it, he said it was a boncer show, the best thing he’d ever been at.