Green’s Dictionary of Slang

(UK juv.) the buttocks, us. a baby’s or small child’s .

1873		Sl. Dict. 94: Botty, [...] an infant’s posterior. Nursery.
1879		Victorian PRO 563 30/3: ‘I was lying down on the bed on my botty. He made me face downwards. He then got on top of me and then he first fucked my backside with his finger’ [Simes:DLSS].
1907		C. Prendergast Sadopaideia 18: Let’s look at the poor little bottie. Turn round, is it much cut up?
1922		Joyce Ulysses 724: Grinning all over his big Dolly face like a well-whipped childs botty.
1924		R. Firbank Prancing Nigger 36: ‘Now she set up a hullabaloo like de time de scorpion bit her botty,’ Mrs Mouth lamented [Simes:DLSS].
1975		D. Nobbs Fall and Rise of Reginald Perrin (1976) 33: ‘Wet botty,’ said Adam.
1982		N. Keesing Lily on the Dustbin 25: Many people listed ‘bottom’ as a genteelism, but gave ‘bum’ as its synonym implying that ‘bottie’ was the politer word.
1993		R. Doyle Paddy Clarke Ha Ha Ha 95: We called them botty bickies sometimes, because of the way the butter came out.
1999		Observer 24 Oct. 29: Claire Short gets her botty publicly smacked.
2006		E. St Aubyn Mothers Milk 11: I’ve changed His Majesty’s nappy so he’ll have a nice dry botty.
2012		Slate 20 Jan. 🌐 While I try desperately to catch a glimpse of Mick’s bottie, my pals focus on the chests of the two ladies.
2021		P Howard Braywatch 36: ‘We got each utter’s nayums tattooed on eer botties as a soyun of eer lub for each utter’.
2023		R. Milward Man-Eating Typewriter 90: I landed at the bottom step [...] bruising my botty.