Tuchus

[justscience]

Also spelled tuchis, toches, tuches, among others.

A grand old Yiddish word for what is always behind you: buttocks. It is often used by non Jewish people as a seemingly more polite or quaint alternative to butt.
Example: Joseph Robert, if you track mud in here again, your tuchus will get a spanking it won't forget.

Sometimes it refers more specifically to the anus, as in: My tuchus hates Mexican food.

[brogine]

Per Leo Rosten’s The Joys of Yiddish, it’s from the Hebrew for ‘under’.