kook

noun

ˈkük 

: one whose ideas or actions are eccentric, fantastic, or insane : screwball

Synonyms

• eccentric
• character
• crackpot
• wacko
• weirdo
• loon
• loony
• nutcase
• nutter [British slang]
• nut
• whacko
• crank
• flake

Examples of kook in a Sentence

a bunch of kooks dressed up in weird costumes

if you insist on painting your house bright orange, everyone will assume you are a kook

Recent Examples on the Web

The kooks of that age believed that Iran-Contra was only just an inkling of the secret government behind the scenes that was preparing to herd Americans into prison camps. —Chris Stirewalt, The Hill, 7 Oct. 2025

At the rose ceremony, Mel hands roses to Roxanne, Debbie, Gerri, Monica P., Monica B., Carol, Peg, Nicolle (of course), Robin, Amy and Terri, with Alexandra the kook among those going home. —Dave Nemetz, TVLine, 24 Sep. 2025

Not the crazy aunt/spell-casting kook who’s going to be film fans’ top Halloween costume this year. —Brian Truitt, USA Today, 9 Aug. 2025

Aster is no longer offering a twist on things that really took place but on fantasies that occurred only in the imaginations of right-wing kooks. —Nate Jones, Vulture, 18 July 2025

Word History

Etymology

by shortening & alteration from cuckoo

First Known Use

1960, in the meaning defined above

Rhymes for kook

• fluke
• juke
• luc
• luke
• nuke
• puke
• souk
• spook
• archduke
• rebuke
• caoutchouc

Kids Definition

kook

noun

ˈkük 

: a person who acts in a strange or foolish way : nut

kooky

ˈkü-kē

adjective