keister

noun

keis·​ter ˈkē-stər 

ˈkī-

variants or less commonly keester

ˈkē-stər 

plural keisters also keesters

informal

: buttocks, rear end sense 2

… Borg took a spectacular dive, landing on his keister.

—Curry Kirkpatrick

Four hours ago I was freezing my keister in the wilderness. Now I'm browsing the entrees in a French-inspired restaurant.

—Andrew Nelson

"… a very easygoing guy with a finely honed intelligence, which I didn't realize until he whipped my keister in Trivial Pursuit."

—Kenneth Turan

Synonyms

• backside
• behind
• booty [slang]
• bootie
• bottom
• breech
• bum
• buns
• butt
• buttocks
• caboose
• can
• cheeks
• derriere
• derrière
• duff
• fanny
• fundament
• hams
• haunches
• heinie [slang]
• hunkers
• nates
• posterior
• rear
• rear end
• rump
• seat
• tail
• tail end
• tush [slang]

Examples of keister in a Sentence

he fell right on his keister in front of the whole crowd

Recent Examples on the Web

Speaking of siblings, throughout this episode Matty dodges calls from her sister Bitsy, and then in the final scene, while stoned off her keister, Matty comes home to find one of Bitsy’s better-than-you-might-expect sugar-free peach pies sitting on the counter. —Noel Murray, Vulture, 27 Feb. 2025

This mindset predictably glosses over the fact not all people can get off their keister and run errands like that. —Steven Aquino, Forbes, 21 Nov. 2024

With fearless, ferocious leads Demi Moore and Margaret Qualley willing to let the camera chop them into chunks of flesh — lips, calves, hair, wrinkles and, yes, keisters — for a film that prioritizes shocks over plot, get ready for a whole lot of their blood and guts too. —Amy Nicholson, Los Angeles Times, 19 Sep. 2024

According to a growing body of research, the health problems associated with sitting—heart disease and diabetes, to name two—aren’t simply the result of these extensive periods on our keisters. —Lydia Denworth, Scientific American, 17 Sep. 2024

Before you get started, position your buck so its head is a little uphill of its keister, if possible, and then turn him belly-up. —Dave Hurteau, Field & Stream, 30 Jan. 2023

In his 15 years as MacGruber, a hapless special ops agent who only occasionally saves the day, Will Forte has attempted to violently dispatch his enemies with rubber bands, Q-tips and a stalk of celery wedged up his keister. —Amy Nicholson, Rolling Stone, 13 Dec. 2021

Slim for people who have the characteristic nonexistent keister of the bony Nordic. —Star Tribune, 23 July 2021

Brayden McNabb took offense that Joel Eriksson Ek was hanging around the crease as Vegas goalie Marc-Andre Fleury covered the puck, so the Golden Knights defenseman knocked the Wild center on his keister late in the second period. —Randy Johnson, Star Tribune, 4 May 2021

Word History

Etymology

English slang keister satchel

First Known Use

circa 1930, in the meaning defined above