mule

UK: /ˈmjuːl/ US: /mjul/ ,(myo̅o̅l)

WordReference Random House Learner's Dictionary of American English © 2025

mule¹ /myul/   n. [countable]

1. Veterinary Diseases, Animal Husbandry an animal produced by a female horse and a male donkey:
   A mule is sterile and cannot produce offspring.
2. Informal Terms a stubborn person.
3. Slang Terms a person paid to carry illegal goods, esp. drugs, for a smuggler.

WordReference Random House Unabridged Dictionary of American English © 2025

mule¹  (myo̅o̅l), n. 

1. Veterinary Diseases, Animal Husbandry the sterile offspring of a female horse and a male donkey, valued as a work animal, having strong muscles, a body shaped like a horse, and donkeylike long ears, small feet, and sure-footedness. Cf. hinny ¹.
2. Animal Husbandry any hybrid between the donkey and the horse.
3. Informal Terms a very stubborn person.
4. Botany any sterile hybrid.
5. Slang Terms a person paid to carry or transport contraband, esp. drugs, for a smuggler.
6. Rail Transport a small locomotive used for pulling rail cars, as in a coal yard or on an industrial site, or for towing, as of ships through canal locks.
7. Textiles Also called spinning mule. a machine for spinning cotton or other fibers into yarn and winding the yarn on spindles.
8. Nautical a large triangular staysail set between two masts and having its clew set well aft.
9. Currency [Numis.] a hybrid coin having the obverse of one issue and the reverse of the succeeding issue, or vice versa.
10. Birds [Biol.] a hybrid, esp. one between the canary and some other finch.

• Latin mūlus (masculine)
• Latin mūla mule (feminine); replacing Old English mūl
• Old French
• Middle English bef. 1000

mule²  (myo̅o̅l), n. 

1. Clothing a lounging slipper that covers the toes and instep or only the instep.
2. a woman's shoe resembling this.

• Middle Dutch mūle
• Middle English: sore spot on the heel, chilblain, perh. 1350–1400

Collins Concise English Dictionary © HarperCollins Publishers::

mule / mjuːl/ noun

1. the sterile offspring of a male donkey and a female horse, used as a beast of burden
   Compare hinny1
2. any hybrid animal: a mule canary
3. Also called: spinning mule a machine invented by Samuel Crompton that spins cotton into yarn and winds the yarn on spindles
4. an obstinate or stubborn person

Etymology: 13th Century: from Old French mul, from Latin mūlus ass, mule

mule / mjuːl/ noun

1. a backless shoe or slipper

Etymology: 16th Century: from Old French from Latin mulleus a magistrate's shoe