Green’s Dictionary of Slang

joanna n.

a piano.

1844		New Sprees of London 14: There are two or three other houses in this neighbourhood [...] where they do the chanting without faking the Joeannia.
1846		Swell’s Night Guide 34: As a sort of whipper-in, music is provided – viz., [...] a joano.
1891		Sporting Times 7 Feb. 3/1: [They] used to come and listen to [...] the row that we made on the regimental joanna.
1900		Marvel XIV:343 June 16: Mrs. Blinker played the joanna lurvly.
1912		A.N. Lyons Clara in DSUE (1984).
1921		N&Q 12 Ser. IX 418: The piano was known as a ‘Joanner’.
1930		(con. 1910–20s) D. Mackenzie Hell’s Kitchen 119: Joanna ... piano.
1927		Eve. Herald (Dublin) 24 Nov. 6/4: The East End tongue is rich in quaint idioms and rhymed slang. [...] ‘Thumping the old joanna’ is the picturesque phrase for performing on the piano.
1943		R. Llewellyn None But the Lonely Heart 127: That’s a fine, large, ripe, old joanna [...] Can you play the piano, Reverend?
a.1945		L. Payne private coll. n.p.: Piana(o) Joanno [sic].
1950		C. Harris Three-Ha’Pence to the Angel 141: You’ll ’ave ter give the old jo’anna a bit more of a bashing.
1960		G.W. Target Teachers (1962) 89: Richie herself off towards the johanna, giving them a smile.
1969		S.T. Kendall Up the Frog 21: ’E’d got a Nervo & Knox [...] ’n’ to top the lot a flippin’ Joanna!
1979		R. Barker Fletcher’s Book of Rhy. Sl. 39: Having a bit of a ding-dong round the old Joanna.
1985		S. Berkoff West in Decadence and Other Plays (1985) 98: ‘Knees Up Mother Brown’ to some joanna that’s the life.
1999		Guardian Weekend 31 July 3: We’d be happily gathered around the old Joanna to this very day.
2002		Indep. Rev. 30 Dec. 4: A supremely accomplished joanna-basher since his teens.
2011		Eve. Standard 16 Mar. 23/3: A rousing turn on the old Joanna by Sir Elton John.