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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, -ers