noun. ['ˈmaɪəsən'] the commonest protein in muscle; a globulin that combines with actin to form actomyosin.
1. Noun, singular or mass These fibers, made up of myosin and actin, are positioned just inside the cell membrane. 2. Adjective Troponin and tropomyosin keep the actin and myosin apart so that your muscles do not remain perpetually contracted.
