/ rəʊˈteɪʃn; NAmE roʊ-/ noun
1.
[ U ] the action of an object moving in a circle around a central fixed point :
the daily rotation of the earth on its axis
2.
[ C ] one complete movement in a circle around a fixed point :
This switch controls the number of rotations per minute.
3.
[ U , C ] the act of regularly changing the thing that is being used in a particular situation, or of changing the person who does a particular job :
crop rotation / the rotation of crops (= changing the crop that is grown on an area of land in order to protect the soil)
Wheat, maize and sugar beet are planted in rotation .
The committee is chaired by all the members in rotation .
► ro·ta·tion·al / -ʃənl; NAmE / adjective [ only before noun ]
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WORD ORIGIN
mid 16th cent.: from Latin rotatio(n-) , from the verb rotare , from rota wheel.