Tennis Buttock

• buns, from Gaelic bun "bottom, base", mounds (cfr. Butte, a geographical mound, known since 1805 in American English, from (Old) French butte "mound, knoll") and orbs - shape-metaphors.
• bund - derived from Punjabi
• bunda - bottom, of Brazilian Portuguese origin.
• butt - the common term for a pair of buttocks (singular, as one body-part; cognate but neither its root nor an abbreviation) in the US, used in everyday speech. It is also acceptable in print.