klaxon \KLAK-suhn\,
noun:
a loud electric horn, formerly used on automobiles, trucks, etc., and now often used as a warning signal.
He invented the Klaxon, a horn that relied on electricity to vibrate a metal diaphragm, emitting a sound that was shrill yet guttural, abrupt yet unending, ugly yet lifesaving.
-- Julie M. Fenster, "The Spirit of Invention," 2009
Everybody has heard a klaxon on a car suddenly begin to sound; I understand it is a short circuit that causes it.
-- James Thurber, "Let Your Mind Alone!," The New Yorker, 1937
Klaxon got its name from an American manufacturing company that made horns for automobiles. It entered English in the early 1900s.
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