idler

Definitions

Cars & Driving

  • noun a gearwheel between a driving and a driven gear in a gear train which may serve to reverse the original direction of rotation of the driven wheel
  • noun a free-turning pulley or wheel which serves to maintain tension in a belt drive

Construction

  • A gear or wheel used to impart a reversal of direction or rotation of a shaft.

Publishing

  • noun a roller on a web press which turns freely
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