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keister

American  
[kee-ster] / ˈki stər /
Or keester

noun

Slang.
  1. the buttocks; rump.


keister British  
/ ˈkiːstə /

noun

  1. the rump; buttocks

  2. a suitcase, trunk, or box

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Etymology

Origin of keister

1880–85; earlier, as underworld argot, handbag, suitcase, safe; of obscure origin, but words meaning “chest, box” are frequently adduced as sources, e.g., kist, German Kiste, Yiddish kestl, etc.

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

This approach immediately and literally backfires, with Ted taking a painful errant kick to the keister.

From Slate • Jul. 31, 2021

I watched Ted Leonsis, just in case he slipped on his keister.

From Washington Post • May 7, 2021

Landing on my keister at 55 finally shook my total faith in myself!

From New York Times • Jan. 4, 2017

That was easily the best fancy-dress fight scene since Jackie Chan whupped keister in a cummerbund in 2002.

From Slate • Feb. 21, 2012

Indeed, at the CIA, keister covering was in full swing long before the attacks of 9/11.

From Time Magazine Archive