What is "mule pulley"

Mule \Mule\ (m[=u]l), n. [F., a she-mule, L. mula, fem. of mulus; cf. Gr. my`klos, mychlo`s. Cf. AS. m[=u]l, fr. L. mulus. Cf. Mulatto.]

1. (Zo["o]l.) A hybrid animal; specifically, one generated between an ass and a mare. Sometimes the term is applied to the offspring of a horse and a she-ass, but that hybrid is more properly termed a hinny. See Hinny.

   Note: Mules are much used as draught animals. They are hardy, and proverbial for stubbornness.

2. (Bot.) A plant or vegetable produced by impregnating the pistil of one species with the pollen or fecundating dust of another; -- called also hybrid.

3. A very stubborn person.

4. A machine, used in factories, for spinning cotton, wool, etc., into yarn or thread and winding it into cops; -- called also jenny and mule-jenny.

5. A slipper that has no fitting around the heel.

   Syn: mules, scuff, scuffs.

   Mule armadillo (Zo["o]l.), a long-eared armadillo (Tatusia hybrida), native of Buenos Ayres; -- called also mulita. See Illust. under Armadillo.

   Mule deer (Zo["o]l.), a large deer ( Cervus macrotis syn. Cariacus macrotis) of the Western United States. The name refers to its long ears.

   Mule pulley (Mach.), an idle pulley for guiding a belt which transmits motion between shafts that are not parallel.

   Mule twist, cotton yarn in cops, as spun on a mule; -- in distinction from yarn spun on a throstle frame.

n. An idle pulley for guiding a belt which transmits motion between shafts that are not parallel.