Definition of pinnation in US English:

pinnation

noun

  • See pinnate

    • ‘The angle of pinnation was found by placing a protractor along the central tendon and measuring the angle of an individual fiber to the nearest 0.5 deg.’
    • ‘Trabs rise steeply or essentially normally to upper surface from ill-defined surface of pinnation that appears to be near gastral margin.’
    • ‘For example, the angle of pinnation of a pinnate muscle may affect the force of contraction.’
    • ‘Anthaspidellid skeleton with surface of pinnation approximately at midwall, from which trabs rise upward and outward, or inward, to meet dermal and gastral surfaces at acute angles.’
    • ‘Trabs rise steeply or sub-vertically from surface of pinnation, which is approximately 1/3-1/4 of wall thickness from gastral margin.’

Pronunciation

pinnation

/piˈnāSHən/