rotator

n. muscle which rotates a limb (Anatomy)

The movement of body structures is accomplished by the contraction of muscles. Muscles may move parts of the skeleton relatively to each other, or may move parts of internal organs relatively to each other. All such movements are classified by the directions in which the affected structures are moved. In human anatomy, all descriptions of position and movement are based on the assumption that the body is in anatomical position.
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n. rotator

n. rotifer

(n.)
that which gives a rotary or rolling motion, as a muscle which partially rotates or turns some part on its axis.
  

(n.)
A revolving reverberatory furnace.