Either of two letters, little yus (Ѧ) and big yus (Ѫ), representing nasal vowel sounds in the Cyrillic alphabet. The only major Slavic language retaining these sounds is Polish, which is written in the Latin alphabet.
Russianюс (jus), from Old Church Slavonic ѫсъ (ǫsъ, “big yus”)
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(8) The Cholym or Chulym Tatars on the Cholym and both the rivers Yus speak a Turkish language with many Mongol and Yakut words, and are more like Mongols than Turks.
(9) The Abakan cMinusinsk Tatars occupied the steppes on the Abakan and Yus in the 17th century, after the withdrawal of the Kirghizes, and represent a mixture with Kaibals (whom Castren considers as partly of Ostiak and partly Samoyedic origin) and Beltirs - also of Finnish origin.