"The official term for this irrational aversion to red-nosed entertainers is coulrophobia. While many are merely creeped out by clowns, the fear runs much deeper for others, affecting their daily lives.
Several theories attempt to explain the origins of the phobia, though none seem definitive. One of the more interesting comes from Kathryn Cillick. She believes most people are afraid of clowns because it's impossible to gauge a clown's true emotions. Thanks to painted-on smiles, people can't distinguish if the clown is as happy as he seems or if he's actually about to bite somebody's face off. "
Omygosh that is SO true. *shudder*