Cyrillic Small Letter Barred O

Cyrillic Small Letter Barred O at U+04E9 represents a lowercase Cyrillic vowel letter used in several non-Slavic Cyrillic alphabets, where it typically denotes a front rounded vowel similar to German ö. It belongs to the Cyrillic block and is the lowercase form of Cyrillic Capital Letter Barred O. Its most common everyday use is in Mongolian Cyrillic, where it is a normal alphabet letter called ө and appears in words such as өөр meaning “other” or “self,” and өдөр meaning “day.” It is also used in Turkic and Uralic languages written with Cyrillic, including Kazakh, Kyrgyz, Tuvan, Altai, Khakas, and Komi-related orthographies, where it commonly marks an ö-like sound distinct from plain о. In dictionaries, language textbooks, maps, names, and transliteration tables, this letter matters because replacing it with ordinary Cyrillic о can change pronunciation and sometimes meaning. It can be visually confused with Latin small o with stroke or other barred-o letters in mixed-script text, but in Cyrillic-language material it functions as its own Cyrillic alphabetic character.