rotation
/rəuˈteɪʃn; ro`teʃən/ n
1
(a) [U] rotating or being rotated 旋转; 转动
the rotation of the Earth 地球的自转.
(b) [C] one complete movement of this type （旋转的）一圈; （一）转
five rotations per hour 每小时旋转五圈.
2 [C, U] regular organized sequence of things or events 轮流; 轮换
the rotation of crops/crop rotation, ie varying the crops grown each year on the same land to avoid exhausting the soil 作物的轮作[轮种].
3 (idm 习语) in rotation in turn; in regular succession 轮流地; 轮番地; 循环地
The chairmanship of the committee changes in rotation. 委员会主席一职是轮流担任的.