Par·kin·son's disease (pärkĭn-sənz) also Par·kin·son disease (-sən)
A progressive disease of the central nervous system, associated with the destruction of brain cells that produce dopamine and characterized by muscle tremors, muscle rigidity or stiffness, abnormally slow movement, and impaired balance and coordination. It usually affects people over the age of 50. Also called paralysis agitans.
[After James Parkinson (1755-1824), British physician.]
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