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general::
Also, the willies. A sensation of horror or repugnance, as in That weird man gives me the creeps, or I get the willies when I hear that dirge music. The first of these colloquial terms alludes to a sensation of something crawling on one's skin. Charles Dickens used it in David Copperfield (1849) to describe a physical ailment: "She was constantly complaining of the cold and of its occasioning a visitation in her back, which she called ‘the creeps.'" But soon after it was used to describe fear and loathing. The variant dates from the late 1800s, and both its allusion and origin are unclear.
American Heritage Idioms