(from the Greek choreia – dance) – a form of hyperkinesis; characterized by involuntary, rapid, irregular movements that occur in various muscle groups; a state of excessive spontaneous movements that occur irregularly, are non-repetitive, random and disorderly in nature. The term is used both to designate independent diseases in which choreic hyperkinesis is the leading manifestation, and to define choreiform syndromes that occur in various diseases. A more severe form of chorea is ballism.