army and navy, n. — Green’s Dictionary of Slang

army and navy n.

[rhy. sl.]

gravy.

[1834		Drogheda Jrnl 10 June 1/2: Friends, sands dollar, want a Colour, / Army, Navy find ’em gravy].
1939		Western Dly Press 12 Apr. 4/3: ‘Army and navy’ for gravy.
1940		Western Dly Press 13 Aug. 3/5: 'Army and Navy' (Gravy).
1960		J. Franklyn Dict. of Rhy. Sl. 33/2: army and navy Gravy. Gravy was plentiful at meal-times in both services. Early 20C.
1971		J. Jones Rhy. Cockney Sl.
1992		R. Puxley Cockney Rabbit.