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adiadochokinesia

American  
[ad-ee-ad-uh-koh-ki-nee-zhuh, -zhee-uh, -zee-uh, -kahy-nee-] / ˌæd iˌæd ə koʊ kɪˈni ʒə, -ʒi ə, -zi ə, -kaɪˈni- /
Also adiadochokinesis

noun

Medicine/Medical.
  1. the inability to perform rapidly alternating muscular movements, as flexion and extension.


Etymology

Origin of adiadochokinesia

a- 6 + Greek diádocho ( s ) successor ( dia- dia- + doch-, variant stem of déchesthai to receive + -os adj. suffix) + -kinesia