Coulrophobia

A specific fear of clowns has sometimes been discussed in terms of a specific phobia. The term is a neologism coined in the context of informal "-phobia lists".

The term is not listed in the World Health Organisation's ICD-10 nor in the American Psychiatric Association's DSM-5 categorisation of disorders.

Clown costumes tend to exaggerate the facial features and some body parts, such as hands and feet and noses. This can be read as monstrous or deformed as easily as it can be read as comical. The significant aberrations in a clown's face may alter a person's appearance so much that it enters the so-called uncanny valley—in which a figure is lifelike enough to be disturbing, but not realistic enough to be pleasant—and thus frightens a child so much that they carry this phobia throughout their adult life.

According to psychology professor Joseph Durwin at California State University, Northridge, young children are "very reactive to a familiar body type with an unfamiliar face". Researchers who have studied the phobia believe there is some correlation to the uncanny valley effect. Additionally, the fact that much clown behavior is "transgressive" (anti-social behavior) can create feelings of unease.

The contemporary "evil clown" archetype developed in the 1980s, notably popularized by Stephen King's It, and perhaps influenced by John Wayne Gacy, a real-life serial killer dubbed the Killer Clown in 1978. Killer Klowns from Outer Space is a 1988 horror comedy dedicated to the topic. The Joker character in the Batman franchise was introduced in 1940, and has developed into one of the most-recognizable and iconic fictional characters in popular culture, leading the Wizard magazine's "100 Greatest Villains of All Time" ranking in 2006.Krusty the Clown (introduced 1989) is an influential parody of Bozo the Clown in The Simpsons. In episode Lisa's First Word (1992), children's fear of clowns features in the form of Bart being traumatized by an inexpertly-built Krusty the Clown themed bed, repeatedly uttering the phrase "can't sleep, clown will eat me...." The phrase inspired an Alice Cooper song in the album Dragontown (2001) and became a popular catchphrase. Websites dedicated to evil clowns and the fear of clowns appeared in the late 1990s.

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