(1) : the action or process of rotating on or as if on an axis or center. (2) : the act or an instance of rotating something. b : one complete turn : the angular displacement required to return a rotating body or figure to its original orientation.
Since this question is asked under 'Geography', I assume you want the definition of the term rotation used in geography.
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Well, in geography or science, <u>rotation</u> is used to define <em>the time period when the Earth </em><em>rotates </em><em>around</em><em> </em>(goes around)<em> its imaginary axis. </em>
The Earth takes about 24 hours (1 day) to complete 1 rotation.
This rotation of the Earth causes the change in day & night.
The Earth moves in a retrograde rotation (meaning, it moves in a clockwise manner).
Rotation also causes deflection in ocean currents & air currents.