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klaxon

American  
[klak-suhn] / ˈklæk sən /
Or claxon

noun

  1. a loud electric horn, formerly used on automobiles, trucks, etc., and now often used as a warning signal.

klaxon British  
/ ˈklæksən /

noun

  1. a type of loud horn formerly used on motor vehicles

"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 klaxon

An Americanism dating back to 1905–10; formerly trademark

Definitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023

Idioms from The American Heritage® Idioms Dictionary copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.