ro·ta·tion /roˈteʃən/ 名詞
1. The act of turning, as a wheel or a solid body on its axis, as distinguished from the progressive motion of a revolving round another body or a distant point; thus, the daily turning of the earth on its axis is a rotation; its annual motion round the sun is a revolution.
2. Any return or succesion in a series.
Moment of rotation. See Moment of inertia, under Moment.
Rotation in office, the practice of changing public officers at frequent intervals by discharges and substitutions.
Rotation of crops, the practices of cultivating an orderly succession of different crops on the same land.
Ro·ta·tion a. Pertaining to, or resulting from, rotation; of the nature of, or characterized by, rotation; as, rotational velocity.
n 1: the act of rotating as if on an axis; "the rotation of the
dancer kept time with the music" [syn: rotary motion]
2: (mathematics) a transformation in which the coordinate axes
are rotated by a fixed angle about the origin
3: a single complete turn (axial or orbital); "the plane made
three rotations before it crashed"; "the revolution of the
earth about the sun takes one year" [syn: revolution, gyration]
4: a planned recurrent sequence (of crops or personnel etc.);
"crop rotation makes a balanced demand on the fertility of
the soil"; "the manager had only four starting pitchers in