Mule

n. animal which is a hybrid of a horse and a donkey; stubborn person; weaving device; type of slipper that leaves the heel exposed

MULE is the MULtilingual Enhancement to GNU Emacs.MULE provides facilities not only for handling text written in many different languages (at least 42 character sets, 53 coding sets, 128 input methods, and 58 languages), but in fact multilingual texts containing several languages in the same buffer. This goes beyond the simple facilities offered by Unicode for representation of multilingual text. MULE also supports input methods, composing display using fonts in various different encodings, changing character syntax and other editing facilities to correspond to local language usage, and more.
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In its common modern meaning, a mule is the offspring of a male donkey and a female horse, which is classified as a kind of F1 hybrid. The reverse, the offspring of a male horse and a female donkey, is called a hinny. The term "mule" (Latin mulus) was formerly applied to the offspring of any two creatures of different species - in modern usage, a "hybrid".
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Noun
1. sterile offspring of a male donkey and a female horse
(hypernym) equine, equid
(member-holonym) Equus, genus Equus
2. a slipper that has no fitting around the heel
(synonym) mules, scuff, scuffs
(hypernym) slipper, carpet slipper

n. mule (Zoology); slipper, house shoe

n. mule, animal which is a hybrid of a horse and a donkey; stubborn person