Green’s Dictionary of Slang

(usu. UK juv.) the stomach; cite 1904 refers to King Edward VII.

1869		W.S. Gilbert ‘Ben Allah Achmet’ Bab Ballads 200: It made him moan – it made him groan [...] Why should I hesitate to own / That pain was in his little tummy?
1885		Bulletin (Sydney) 23 May 18/4: When his pupils ’rithmetic required repairs, or their grammar was out of gear, the sage preceptor viewed the matter as a case of derangement of their little tummies, and forthwith punished them not with the cane, but with a spoon containing castor oil.
1904		Sun. Times (Perth) 10 Jan. 1/3: [headline] Tummy’s Trip.
1915		‘Ian Hay’ First Hundred Thousand (1918) 199: Rotten work, marching or fighting on a hollow tummy!
1922		Joyce Ulysses 144: A sugarsticky girl shovelling scoopfuls of creams for a christian brother. Some school treat. Bad for their tummies.
1934		Wodehouse Right Ho, Jeeves 166: It now looked probable that there would shortly be aching tummies.
1945		G. Fairlie Capt. Bulldog Drummond 135: I didn’t know whether it’s because my tummy has lost the habit [...] but I just can’t eat any more.
1958		P. Larkin letter 21 Oct. in Thwaite Sel. Letters (1992) 290: The Sunday Express tells me girls are a new shape now – bushy heads, big tummies, long legs.
1987		‘Victoria Parker’ Pay for Play Cheerleaders 🌐 Gawd, your prick is on my tummy.
1999		K. Sampson Powder 273: I’m going to dab my cock all over your tummy.
2000		Indep. Rev. 12 Jan. 8: They use a jolly vocabulary of ‘tummies’ and ‘down below.’.