Mule

1. (Zoöl.) 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.
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.
Mule armadillo (Zoöl.),
a long-eared armadillo (Tatusia hybrida), native of Buenos Ayres; -- called also mulita. See Illust. under Armadillo.
Mule deer (Zoöl.),
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.