Definition of sarcomere in English:



  • A structural unit of a myofibril in striated muscle, consisting of a dark band and the nearer half of each adjacent pale band.

    • ‘Gradually, new sarcomeres (contractile units) are laid down to share the work load and reduce the wall stress.’
    • ‘The actin filaments found in the sarcomeres of striated muscles, as well as in stress fibers and microvilli in nonmuscle cells, are stable, unbranched structures.’
    • ‘Line scans were determined for portions of myofibrils that were straight, contained five or more sarcomeres, and had striations relatively perpendicular to the long axis of the myofibril.’
    • ‘Factors contributing to the additional improvement include increases in oxygenation, right ventricular function, cardiac output, number of sarcomeres, and muscle mass, and a decrease in glucocorticoid use.’
    • ‘Electron microscopy was used to examine ultrastructural evidence of injury, including sarcomeric disruption, disorganisation of myofilaments, misalignment of adjacent sarcomeres, and distortion or absence of Z-lines.’


Late 19th century: from Greek sarx, sark- ‘flesh’ + meros ‘part’.