Green’s Dictionary of Slang

1. the heart.

1892		‘Doss Chiderdoss’ ‘The Rhyme of the Rusher’ in Sporting Times 29 Oct. n.p.: Then I sallied forth with a careless air, / And contented raspberry tart.
1900		Sporting Times 24 Mar. 2/2: In their midst—be still my palpitating cherry-tart—stood their instructress, a dear, tony little, wicked-eyed divinity.
1923		Eve. Teleg. (Dundee) 11 July 11/4: Raspberry (raspberry tart) means a heart.
1932		‘P.P.’ Rhy. Sl.
1938		(con. 1900s) in J.B. Booth Sporting Times 87: A tear-drop fell from the girl’s mince-pie, And her raspberry-tart was torn.
1946		St.V. Troubridge ‘Some Notes on Rhyming Argot’ in AS XXI:1 Feb. 46: i desire. A fire. (English, 1900.) Anna Maria is ten times as usual. The best known poem in rhyming slang begins: As I sat in front of the Anna Maria, / Warming me plates of meat, / There came a knock at the Rory O’More / That made me old raspberry beat.
1957		G. Kersh Fowlers End (2001) 268: My poor mince pies are full o’ tears / My raspberry tart is jelly.
1963		L.F. Freed Crime in S. Afr. 106: His ‘raspberry tart’ his heart.
1969		S.T. Kendall Up the Frog 22: There comes a knock at the Rory O’Moore / That made me raspberry tart beat.
1978		F. Norman Dead Butler Caper 102: Spats plugged Machin-Gun Jack froo the strawberry tart wiv ’is 45.

2. (also rarzer, rarzo, razzo) an act of breaking wind [= fart n. (1)].

1959		I. & P. Opie Lore and Lang. of Schoolchildren (1977) 28: When a child, as a sign of derision, expels air through his compressed lips, the stock report is ‘We have them with custard.’ The chain here is that breaking wind was, at one time, [...] known as a ‘raspberry tart’, hence ‘raspberry’.
1971		F.J. Hardy Outcasts of Foolgarah (1975) 34: I had a Jack the Ripper for breakfast and it’s made me raspberry tart.
1984		Partridge DSUE (8th edn) 677/1: Let go a razzo. To break wind [...] Razzo, rarzer and rarzo are all var. abbr. of raspberry (tart).
1989		H. Rawson Dict. of Invective (1991) 322: Raspberry is short for raspberry tart, with the tart part being Cockney rhyming slang for the noise that is made when a person vents, or breaks, what is politely called ‘wind’.
2002		D. Shaw ‘Dead Beard’ at www.asstr.org 🌐 ‘No more, Harry, no more, I can’t take anymore,’ she tells me. ‘If I have a raspberry tart right now I’ll split open!’.
2008		N. Drayson Birds East Africa 28: ‘Are we talking a delicate little Scandinavian pfft, or the whole raspberry tart?’ .