Green’s Dictionary of Slang

mother and daughter n.

water.

1859		Hotten Dict. of Modern Sl. etc.
1864, 1867, 1870		Hotten Sl. Dict.
1873		Sl. Dict.
1909		J. Ware Passing Eng. of the Victorian Era 177/2: Mother (Complicated Rhyming, 1868). Water. Abbreviation of ‘mother and daughter.’.
1935		A.J. Pollock Und. Speaks.
1946		St. Vincent Troubridge ‘Some Notes on Rhyming Argot’ in AS XXI:1 Feb. 46: mother and daughter. Water. (Origin doubtful, probably English.) This again, if English, is rare. I have never heard anything except ratcatcher’s daughter (from a popular song of the 1850’s), or didn’t ought ter.
1949		Monteleone Criminal Sl. (rev. edn).
1951		E. Hill Territory 446: You take the drive-me-silly and go down to the bubble-and-squeak and get some mother-and-daughter, and I’ll light the Molly Maguire and we’ll have some Gypsy Lee.
1953		Berrey & Van den Bark Amer. Thes. Sl. (2nd edn).
1963		L.F. Freed Crime in S. Afr. 106: When he asks for ‘mother and daughter’ he means that he wants water.
1968		J. Alard He who Shoots Last 96: Wot d’ya wants me to do? Stand in da corner wif a glass of mudder and daughter in me claw?
1972		Dodson & Saczek Dict. of Cockney Rhy. Sl.
1984		J. Meredith Learn to Talk Old Jack Lang 19: So I threw off my barrel of fat, dicky dirt, rammy rousers and daisy roots, and dived into the mother and daughter.
2002		Pete’s Aussie Sl. Home Page 🌐 mother and daughter: water.