Green’s Dictionary of Slang

1. (Aus.) someone or something excellent, outstanding, also as adj.

1894		Aus. Star (Sydney) 9 June 3/2: Mr. Richards will introduce to Australia an up to date London ditty, catchily called ‘Clamber Closer Clara,’ which is described [...] as a ‘regular rumpty-tummer,’ whatever that may be.
1908		Molong Exp. (NSW) 10 Oct. 11/3: They paraded the ladies in animal fashion, and the best fancy dress was a very ‘rumpty’ one.
1915		Table Talk (Melbourne) 21 Oct. 33/2: Lavendo is now the real boss-pup of the racing heap—‘a rumpty-tummer’ in every way.
1917		Eve. Post 10 Oct. 10/6: A rumprtty tummer is Barcelona. He is a real horse and Clarke has him well.
1922		Table Talk (Melbourne) 9 Mar. 37/2: Yet they handed out the boodle with a smile as bright as summer, / For the rorty racer Rostrum who's a regular rumpty-tummer.
1931		Sydney Sportsman (Surry Hills, NSW) 24 Nov. 5/2: What a Galloper! Saturday’s Maiden field at Warwick was a rumpty-hummer.
1933		Truth (Sydney) 13 Aug. 2/4: There's no closing your eyes to the fact that Balgay is a rumpty hummer [...] he would start an even money elect and probably win it by ‘half the straight’.
1945		AEF Times 5 Feb. 45/4: It’s a rumpty.
1939		Eve. Post 4 Feb. 22/5: We have been told that the Viking’s Christmas trip was a ‘rumpty’ in more ways than one.
1941		Baker Popular Dict. Aus. Sl.
1959		G. Slatter Gun in My Hand 200: I’ve seen some rumpty parties in kitchens. Real humdingers.
1972		Canberra Times (ACT) 21 July 16/3: The high schools’ match between Daramalan and Epping at 2pm today should be a rumpty.
2003		McGill Reed Dict. of N.Z. Sl. 176: rumpty Anything excellent, including sexual, sometimes rumptydooler. ANZ variation of ‘rumtitum’ from early C20.

2. (Aus.) a verbose (if insincere) talker, a braggart.

1903		Sun. Times (Perth) 8 Nov. 4/5: He wrote to Adelaide in hot haste to explain that ‘Ten Foot’ [i.e. a politician] was a rumpty-tummer much addicted to talking through his neck.
1906		Tocsin (Melbourne) 16 Aug. 2/1: Rumpty Reid came to Queen land to teach people the necessity of polling their votes [...] yet all his advocacy in New South Wales, his own State, has resulted in its being one of the worst voting States in the Commonwealth.
1912		Sun. Times (Perth) 1 Dec. 4/5: The union secretary [...] is regarded as a ‘rumpty-tummer,’ [...] a ‘Them’s-my-sentiments-and-if-you don’t-like-them-they-can-be-altered’ sort of bloke.

3. (N.Z.) broken down, unattractive, disreputable.

1906		NZ Truth 4 Aug. 6/2: These rumpty roosters made out of lewdness.
1918		Colonist (NZ) 21 June 7/4: ‘To beetle round in a rumpty’ [...] means to flop about in the air in a certain type of old-fashioned almost fool-proof machine, offcially known as a Maurice-Farman, but popularly alluded to as a rumpty .
1950, 1958		informants in DNZE (1998).
1985		National Radio (Correspondence School) 4 Nov. in DNZE (1998) 685/3: (A story in NZ speech includes:) Baching in a rumpty old shack .
1995		Dominion (Wellington) 20 Sept. 36: Turner [NZ cricket coach] was not unduly concerned about the size of the [NZ] defeat. ‘It was a pretty rumpty wicket, we didn’t take good advantage of it and they did.’ [DNZE].