Definition of "pulley"
pulley
/ˈpʊli/
noun
plural pulleys or (obsolete) pullies
(engineering, countable) One of the simple machines; a sheave, a wheel with a grooved rim, in which a pulled rope or chain lifts an object (more useful when two or more pulleys are used together, as in a block and tackle arrangement, such that a small force moving through a greater distance can exert a larger force through a smaller distance).