- The definition of a pulley is a small fixed wheel or a group of such wheels with a rope or chain in a grooved rim that is used to lift something up.
An example of a pulley is a device for raising a flag.
pulley definition by Webster's New World
- a small fixed wheel, sometimes turning in a block, with a grooved rim in which a rope or chain runs, as to raise a weight attached at one end by pulling on the other end: it changes the direction of effort but provides no mechanical advantage
- a combination of such wheels, used to increase the mechanical advantage
- a wheel that turns or is turned by a belt, rope, chain, etc., so as to transmit power
Origin: Middle English poley ; from Old French polie ; from Midieval Latin poleia ; from poledia ; from Medieval Greek an unverified form polidion, diminutive of polos, pivot, windlass, axis: see wheel
pulley definition by American Heritage Dictionary
noun pl. pul·leys
- A simple machine consisting essentially of a wheel with a grooved rim in which a pulled rope or chain can run to change the direction of the pull and thereby lift a load.
- A wheel turned by or driving a belt.
Origin: Middle English poley, from Old French polie and from Medieval Latin poliva, both ultimately from Greek polos, axis; see kwel-1 in Indo-European roots.
pulley - Science Definition