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Synonyms

bonkers

American  
[bong-kerz] / ˈbɒŋ kərz /

adjective

Slang.
  1. mentally unbalanced; mad; crazy.


bonkers British  
/ ˈbɒŋkəz /

adjective

  1. slang mad; crazy

"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

Usage

Where does the word bonkers come from? Bonkers is a funny-sounding word. It's a goofy, lighter, informal way to say "crazy" or "nuts”—but keep in mind that’s it not so fun to make fun of people’s mental health. Its origins are unclear, but bonkers is first recorded as British naval slang for "a bit drunk" in the 1940s—perhaps acting like someone has bonked, or hit, them on the head. The roots of these other words may get a rise—of laughter or surprise—out of you. Run on over to our roundup of them at "Weird Word Origins That Will Make Your Family Laugh."

Etymology

Origin of bonkers

1945–50; of uncertain origin; for final element, cf. -ers

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.

The mysterious finances of Musk’s company were detailed this week in SpaceX’s IPO filing, which is far more bonkers than financial paperwork has any right to be.

From The Wall Street Journal • May 22, 2026

It’s the more bonkers elements that make this movie sing and that grinning, ghoulish sensibility proves to be Sokolov’s auteurist signature.

From Los Angeles Times • Mar. 26, 2026

It wasn’t even an official WBC game—and the scenes were bonkers.

From The Wall Street Journal • Mar. 5, 2026

"On one hand, it's a bit bonkers, but on the other it's a monument to the impact Ianto, and his relationship with Jack, had on the queer community, and one that I'm really proud of."

From BBC • Mar. 4, 2026

“Yo, man,” Vega said, “I hope that girl don’t go bonkers on you up in the center, man.”

From "The Stars Beneath Our Feet" by David Barclay Moore

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