Ataxia (from Greek α- + -τάξις, meaning "lack of order") is a neurological sign and symptom that consists of gross lack of coordination of muscle movements. Ataxia is a non-specific clinical manifestation implying dysfunction of the parts of the nervous system that coordinate movement, such as the cerebellum. Several possible causes exist for these patterns of neurological dysfunction. The term "dystaxia" is a rarely used synonym. The International Ataxia Awareness Day is observed on September 25 each year.