Entry 1 sense Webster, 1913 akinesia /(ā`kĭ*nē"sē*ȧ or ăk`ĭ*nē"sĭ*ȧ)/ · ak·i·ne·si·a · IPA 01 n. Loss of the ability for voluntary muscle movement. 1. Loss of the ability for voluntary muscle movement.(Med.)