pulley

[ poo l-ee ]
/ ˈpʊl i /

noun, plural pul·leys.

a wheel, with a grooved rim for carrying a line, that turns in a frame or block and serves to change the direction of or to transmit force, as when one end of the line is pulled to raise a weight at the other end: one of the simple machines.
a combination of such wheels in a block, or of such wheels or blocks in a tackle, to increase the force applied.
a wheel driven by or driving a belt or the like, used to deliver force to a machine, another belt, etc., at a certain speed and torque.

RELATED WORDS

Origin of pulley

1275–1325; Middle English poley, puly < Middle French polieMedieval Greek *polídion little pivot, equivalent to pól(os) pole2 + -idion diminutive suffix

Related forms

pul·ley·less, adjective
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019

Examples from the Web for pulley

British Dictionary definitions for pulley

pulley

/ (ˈpʊlɪ) /

noun

a wheel with a grooved rim in which a rope, chain, or belt can run in order to change the direction or point of application of a force applied to the rope, etc
a number of such wheels pivoted in parallel in a block, used to raise heavy loads
a wheel with a flat, convex, or grooved rim mounted on a shaft and driven by or driving a belt passing around it

Word Origin for pulley

C14 poley, from Old French polie, from Vulgar Latin polidium (unattested), apparently from Late Greek polidion (unattested) a little pole, from Greek polos axis
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Science definitions for pulley

pulley

[ pulē ]

A machine consisting of a wheel over which a pulled rope or chain runs to change the direction of the pull used for lifting a load. Combinations of two or more pulleys working together reduce the force needed to lift a load. See also block and tackle.
The American Heritage® Science Dictionary Copyright © 2011. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.