myuuru means "Mule" in English.
It's a katakanization, a loan-word.

myuuru in katakana is ミュール.
myuuru is not usually written with hiragana.
myuuru does not have kanji.
Romaji myuu ru
Katakana ミュ

Orthography Notes

  • ミュ is a compound kana representing a single syllable with multiple characters.
  • ミュー contains a long dash called the prolonged sound mark which makes the vowel of the syllable longer. Because of this, this word may also be romanized as myūru.
Wikipedia: 騾馬


raba ラバ.