Dysdiadochokinesia

Dysdiadochokinesia, dysdiadochokinesis, dysdiadokokinesia, dysdiadokokinesis (from Greek dys "bad", diadocho "receive", kinesia "movement"), often abbreviated as DDK, is the medical term for an impaired ability to perform rapid, alternating movements. Inability to perform the rapid alternating movements is called adiadochokinesia.