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Medical Term:


Pronunciation: bal-iz′mŭs

Definition: A type of involuntary movement affecting the proximal limb musculature, manifested in jerking, flinging movements of the extremity; caused by a lesion of or near the contralateral subthalamic nucleus. Usually only one side of the body is involved, resulting in hemiballismus.

Synonym(s): ballism

[G. ballismos, a jumping about]