an expression for someone who overuses his vehicle's horn, specifically holding it down for more than a second at a time.

a horn happy person is usually particularly impatient on the road, and doesn't understand that holding down a vehicle's horn is an aggressive action that causes physical discomfort and harm to people (pedestrians, cyclists and rollerbladers) in the immediate vicinity of the car, in addition to irritating people who live in the area.

horn happy people are usually unaware of just how little actual value is added by their hooting - a typical result of a lengthy hoot is the slowing down or stopping of the person in front to see what all the trouble is.
i'd like to report that horn happy bastard - my ears are ringing!
by geek.neo April 25, 2010
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