Tooshy

To the small child, feces and urine done in the diaper are warm and moist also. “No toilet!” protests a verbal two-year-old. “Why, darling?” “No, no, Mommy. It makes my tooshy too cold.”

Source: wiktionary

“Well, I’m certainly not going to go traipsing down there and get my tooshy shot off.”

Source: wiktionary

When Mr. Leiter falls he also makes a joke about hurting his “tooshy.”

Source: wiktionary

‘Eyes in her toochus, this one,’ Gus said admiringly. […] George laughed as she followed Gus and reached out to pinch his own bottom hard. ‘Since when did you learn to speak American? This is your tooshy, not your however you said it.’

Source: wiktionary