myosin

n. commonest protein which constitutes the muscles and facilitates muscle contraction (Medicine)

Myosins are a large family of motor proteins found in eukaryotic tissues. They are responsible for actin-based motility.
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Myosin /my·o·sin/ a protein of the myofibril, occurring chiefly in the A band; with actin it forms actomyosin, which is responsible for the [more]Myosin - Community and Resources

Noun
1. the commonest protein in muscle; a globulin that combines with actin to form actomyosin
(hypernym) globulin
(substance-holonym) actomyosin

n. myosin, commonest protein which constitutes the muscles and facilitates muscle contraction (Medicine)