alternating tremor

al·ter·nat·ing trem·or

a form of hyperkinesia characterized by regular, symmetric, to-and-fro movements (at about 4 per second) that are produced by patterned, alternating contraction of muscles and their antagonists.

al·ter·nat·ing trem·or

(awl'tĕr-nāt-ing trem'ŏr) A form of hyperkinesia characterized by regular, symmetric, to-and-fro movements (at about 4 per second) that are produced by patterned, alternating contractions of muscles and their antagonists.