Green’s Dictionary of Slang

1. (orig. milit.) tea.

1916		Yorks Eve. Post 16 Oct. 5/4: The jargon of the ‘Tommy’ [...] is a never-ending source of wonder to canteen workers and barmaids [...] A cup of tea becomes ‘Rosy Lee’.
1925		(con. WWI) Fraser & Gibbons Soldier and Sailor Words 246: Rosy Lee: Tea.
1929		J.B. Priestley Good Companions 133: ’Ow about a drop o’ Rosie Lee? [Ibid.] 134: We’ll ’ave the Rosie now, George.
1934		P. Allingham Cheapjack 164: We had a cup o’ rosy together.
1938		J. Curtis They Drive by Night 99: One smashing cup of Rosy Lee for the little lady.
1943		‘Henry Green’ Caught (2001) 113: I could do with a nice cup of Rosie Lee.
a.1945		L. Payne private coll. n.p.: Tea Rosy Lea.
1945		(con. 1937) R. Westerby Mad in Pursuit 158: ’Ave a cuppa Rosy?
1945		J. Maclaren-Ross Swag, the Spy and the Soldier in Lehmann Penguin New Writing No. 26 38: There was also rhyming slang: [...] tea itself was Rosy Lee.
1953		J. Franklyn Cockney 293: After he had his Rosy Lea (tea) he took a Martin-le-Crand (hand) at Wilkie Bards (cards).
1957		G. Kersh Fowlers End (2001) 268: On the Johnny Horner I must stand / In this land of the yet-to-be, / ’Olding out my Martin’s-le-Grand / For the price of a Rosie Lee.
1958		(con. 1940s) B. Behan Borstal Boy 321: It’s getting on for break [...] how about the Rosy Lee?
1962		R. Cook Crust on its Uppers 21: Ever had someone put some snout ash in your rosie?
1971		F.J. Hardy Outcasts of Foolgarah (1975) 24: Get some glasses, Flo, we don’t drink Rosy Lee or pig’s ear tonight, we drink champers.
1977		S. Berkoff East in Decadence and Other Plays (1985) 61: Parlering for another cup of rosy.
1979		F. Norman Too Many Crooks Spoil the Caper 164: It was the only place in Soho where you could get a cup of Rosey Lee and a Telfer’s meat pie on Christmas Day.
1980		(con. 1930s) Barltrop & Wolveridge Muvver Tongue 21: Rosie Lea, you-and-me : tea.
1984		(con. WW2) T. Jones Heart of Oak [ebook] Here you are then, Wings, cup of the old Rosy Lee, and get this here oggie under your blooming belt, my son.
1995		J. Cameron Vinnie Got Blown Away 22: Came back on crime for a second cup of rosie.
2000		Sun. Times News Rev. 12 Mar. 1: He managed not to offer me a cup of ‘Rosy.’.
2001		Guardian G2 28 Nov. 4: Chips, saveloys and cups of Rosie Lee.
2001		K. Sampson Outlaws (ms.) 44: She’s [...] dunking her toast into a fresh mug of rosie.

2. a flea.

1984

Partridge DSUE (8th edn) 989/1: C.20.