Tennis Buttock

• bum - in British English, used frequently in the United Kingdom, Ireland, Canada, Australia, New Zealand and many other English speaking Commonwealth countries, also historically in U.S., is a mild often humorous reference to buttocks, not necessarily in vulgar or sexual context: "I've a boil on my bum, thrice as large as my thumb" - The Judge With The Sore Rump, St. George Tucker. Also used in reference to anal intercourse, often as an insult, as in bum boy (for a homosexual). Also a verb - to practise anal intercourse.
• 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.