rotation

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ro·ta·tion / rōˈtāshən/ • n. the action of rotating around an axis or center: the moon moves in the same direction as the earth's rotation. ∎  (also crop ro·ta·tion) the action or system of rotating crops. ∎  Forestry the cycle of planting, felling, and replanting. ∎  the passing of a privilege or responsibility from one member of a group to another in a regularly recurring succession: it has become common for senior academics to act as heads of department in rotation. ∎  a tour of duty, esp. by a medical practitioner in training: she was completing a rotation in trauma surgery. ∎  Math. the conceptual operation of turning a system around an axis. ∎  Math. another term for curl (sense 2). DERIVATIVES: ro·ta·tion·al / -shənl/ adj. ro·ta·tion·al·ly / -shənl-ē/ adv.

rotation The turning of a body on its axis, such as the daily rotation of the Earth. It is usually measured relative to the stars, and termed the sidereal period of axial rotation.

rotation Turning of a body about its axis. In the Solar System, the Sun and all the planets, with the exception of Uranus and Venus, rotate from w to e.

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