# O (Cyrillic)

The Cyrillic script :
Slavic letters :
| А | А̂ | А̄ | Ӑ | Ӓ | Б | В | Г |
| Ґ | Д | Ђ | Ѓ | Е | Е̂ | Е̄ | Ё |
| Є | Є́ | Ж | З | З́ | Ѕ | И | І |
| І́ | Ї | Ꙇ | И̂ | Ӣ | Й | Ӥ | Ј |
| К | Л | Љ | М | Н | Њ | О | О̂ |
| О̄ | Ӧ | П | Р | С | С́ | Т | Ћ |
| Ќ | У | У̂ | Ӯ | Ў | Ӱ | Ф | Х |
| Ц | Ч | Џ | Ш | Щ | Ꙏ | Ъ | Ы |
| Ь | Э | Ю | Я | ʼ | ˮ | | |
Non-Slavic letters :
| А̊ | А̃ | Ӓ̄ | Ӕ | Ә | Ә̃ | Ӛ | В̌ |
| Ԝ | Г̑ | Г̇ | Г̣ | Г̌ | Г̂ | Г̆ | Г̈ |
| Г̊ | Ҕ | Ғ | | Ӻ | Ғ̌ | Ғ̊ | Ӷ |
| Г̡ | Д́ | Д̌ | Д̈ | Д̣ | Д̆ | Ӗ | Е̃ |
| Ё̄ | Є̈ | Ԑ | Ԑ̈ | Җ | Ӝ | Ӂ | Ж̣ |
| Ҙ | Ӟ | З̌ | З̣ | З̆ | Ӡ | И̃ | И̇ |
| Ҋ | Қ | Ӄ | Ҡ | Ҟ | Ҝ | К̣ | К̊ |
| Қ̊ | Ԛ | ᴫ | Л́ | Ӆ | Ԯ | Ԓ | Л̈ |
| Ӎ | ᵸ | Н́ | Ӊ | Ң | Ԩ | Ӈ | Ҥ |
| О̆ | О̃ | Ӧ̄ | Ө | Ө̄ | Ө́ | Ө̆ | Ӫ |
| Ԥ | П̈ | Р̌ | Ҏ | С̌ | Ҫ | С̣ | С̱ |
| Т́ | Т̈ | Т̌ | Т̇ | Т̣ | Ҭ | Ᲊ | У̃ |
| У̌ | Ӳ | У̊ | Ӱ̄ | Ұ | Ү | Ү́ | Х̣ |
| Х̱ | Х̮ | Х̑ | Х̌ | Ҳ | Ӽ | Х̊ | Ӿ |
| Ӿ̊ | Һ | Һ̈ | Ԧ | Ц̌ | Ц̈ | Ҵ | Ҷ |
| Ҷ̣ | Ӵ | Ӌ | | Ҹ | Ч̇ | Ч̣ | Ҽ |
| Ҿ | Ш̣ | ꚜ | Ы̆ | Ы̄ | Ӹ | ꚝ | Ҍ |
| Ҩ | Э̄ | Э̇ | Ӭ | Ӭ́ | Ӭ̄ | Ю̆ | Ю̈ |
| Ю̄ | Я̆ | Я̄ | Я̈ | Ӏ | | | |
Archaic or unused letters :
А̨Б̀Б̣Б̱В̀Г̀Г̧Г̄Г̓Г̆Ҕ̀Ҕ̆ԀД̓Д̀Д̨ԂꚀꙢЕ̇Е̨Ж̀Ж̑ꙂꙄЏ̆ꚄꚄ̆ꙀЗ̀З̑ԄԆꚈԪꚂꚔІ̂І̣І̨Ј̵Ј̃ꙈК̓К̀К̆Ӄ̆К̑К̇К̈К̄ԞК̂Л̀ԠꙤԈЛ̑Л̇ԔМ̀М̃ꙦН̀Н̄Н̧Н̃ԊԢН̡ѺꙨꙪꙬꙮꚘꚚП̓П̀П́ҦП̧П̑ҀԚ̆Р́Р̀Р̃ԖС̀С̈ԌҪ̓Т̓Т̀ԎТ̑ꚊТ̧ꚌꚌ̆ѸꙊУ̇У̨ꙋ́Ф̑Ф̓Х́Х̀Х̆Х̇Х̧Х̾Х̓һ̱ѠꙌѼѾꙠЦ̀Ц́Ц̓ꚎꚎ̆ꚐЧ́Ч̀Ч̆Ч̑Ч̓ԬꚒꚆꚆ̆Ҽ̆Ш̀Ш̆Ш̑Щ̆ꚖꚖ̆Ъ̄Ъ̈Ъ̈̄ꙐЫ̂Ы̃ѢѢ́Ѣ̈Ѣ̆ꙒЭ̨Э̂ꙔЮ̂ꙖЯ̈Я̂Я̨ԘѤѦꙘѪꙚѨꙜѬѮѰѲѴѶꙞ :
List of Cyrillic letters
List of Cyrillic multigraphs :
vte :
O (О о; italics: О о) is a letter of the Cyrillic script.
The letter most commonly represents the sound /ɔ/, like the o in "off". In Russian and Serbo-Croatian, it represents the sound /o/.

## History

The Cyrillic letter О was derived from the Greek letter Omicron (Ο ο).

## Form
### Modern fonts

In modern-style typefaces, the Cyrillic letter O looks exactly like the Latin letter O ⟨O o⟩ and the Greek letter Omicron ⟨Ο ο⟩.

### Church Slavonic printed fonts and Slavonic manuscripts

Historical typefaces (like poluustav (semi-uncial), a standard font style for the Church Slavonic typography) and old manuscripts represent several additional glyph variants of Cyrillic O, both for decorative and orthographic (sometimes also "hieroglyphic") purposes, namely:
* broad variant (Ѻ/ѻ), used mostly as a word initial letter (see Broad On for more details);
* narrow variant, ᲂ, being used now in Synodal Church Slavonic editions as the first element of digraph Oy/oy (see Uk (Cyrillic) for more details), and in the editions of Old Believers for unstressed "o" as well;
* variant with a cross inside (Crossed O), Ꚛ, used in certain manuscripts as the initial letter of words окрестъ 'around, nearby' (the root of this Slavonic word, крест, means 'cross') and округъ 'district, neighbourhood' with their derivatives;
* "eyed" variant (Monocular O) with a dot inside (Ꙩ/ꙩ), used in certain manuscripts in spelling of word око 'eye' and its derivatives. In many other texts, including the birchbark letters, the monocular O was not used as a hieroglyph but largely as a synonym of Broad On signalling the word-initial position;
* "two-eyed" variants (Binocular O) with two dots inside (Ꙫ/ꙫ or Ꙭ/ꙭ), also double "O" without dots inside were used in certain manuscripts in spelling of dual/plural forms of the words with the same root 'eye';
* "many-eyed" variant (Multiocular O), ꙮ, used in certain manuscripts in spelling of the same root when embedded into word многоочитый 'many-eyed' (an attribute of seraphim).

## Usage

In Russian, O is used word-initially, after another vowel, and after non-palatalized consonants. Because of a vowel reduction processes, the Russian /o/ phoneme may have a number of pronunciations in unstressed syllables, including [ɐ] and [ə].
In Macedonian, Bulgarian, Ukrainian and Belarusian, the letter represents the sound /ɔ/.
In Tuvan the Cyrillic letter can be written as a double vowel. It's the most common letter in the Russian language.

## Related letters and other similar characters

* Ο ο : Greek letter Omicron
* O o : Latin letter O
* Ó ó : Latin letter Ó
* 0 : Digit Zero
* Ё ё : Cyrillic letter Yo
* Ѻ ѻ : Cyrillic letter Broad On
* Ӧ ӧ : Cyrillic letter O with diaeresis
* Ө ө : Cyrillic letter Oe
* Ӫ ӫ : Cyrillic letter Oe with diaeresis
* Ҩ ҩ : Cyrillic letter O-hook

## Computing codes

Character information :
| Preview | О | О | о | о |
| Unicode name | CYRILLIC CAPITAL LETTER O | CYRILLIC CAPITAL LETTER O | CYRILLIC SMALL LETTER O | CYRILLIC SMALL LETTER O |
| Encodings | decimal | hex | dec | hex |
| Unicode | 1054 | U+041E | 1086 | U+043E |
| UTF-8 | 208 158 | D0 9E | 208 190 | D0 BE |
| Numeric character reference | &#1054; | &#x41E; | &#1086; | &#x43E; |
| Named character reference | &Ocy; | &Ocy; | &ocy; | &ocy; |
| KOI8-R and KOI8-U | 239 | EF | 207 | CF |
| Code page 855 | 215 | D7 | 214 | D6 |
| Windows-1251 | 206 | CE | 238 | EE |
| ISO-8859-5 | 190 | BE | 222 | DE |
| Macintosh Cyrillic | 142 | 8E | 238 | EE |
Exotic glyph variants of Cyrillic O are available only in Unicode:
* broad Ѻ/ѻ:
** CYRILLIC CAPITAL LETTER ROUND OMEGA: U+047A
** CYRILLIC SMALL LETTER ROUND OMEGA: U+047B
* narrow ᲂ does not just represent itself, but also used in digraph Oy/oy:
** CYRILLIC SMALL LETTER NARROW O: U+1C82
** CYRILLIC CAPITAL LETTER UK: U+0478 (deprecated in favor of combination of Cyrillic letters О and у, U+041E U+0443)
** CYRILLIC SMALL LETTER UK: U+0479 (deprecated in favor of combination of Cyrillic letters о and у, U+043E U+0443 or U+1C82 U+0443)
* with a cross inside (Ꚛ/ꚛ):
** CYRILLIC CAPITAL LETTER CROSSED O: U+A69A
** CYRILLIC SMALL LETTER CROSSED O: U+A69B
* doubled Ꚙ/ꚙ:
** CYRILLIC CAPITAL LETTER DOUBLE O: U+A698
** CYRILLIC SMALL LETTER DOUBLE O: U+A699
* eyed Ꙩ/ꙩ:
** CYRILLIC CAPITAL LETTER MONOCULAR O: U+A668
** CYRILLIC SMALL LETTER MONOCULAR O: U+A669
* two-eyed (Ꙫ/ꙫ, Ꙭ/ꙭ):
** CYRILLIC CAPITAL LETTER BINOCULAR O: U+A66A
** CYRILLIC SMALL LETTER BINOCULAR O: U+A66B
** CYRILLIC CAPITAL LETTER DOUBLE MONOCULAR O: U+A66C
** CYRILLIC SMALL LETTER DOUBLE MONOCULAR O: U+A66D
* many-eyed ꙮ:
** CYRILLIC LETTER MULTIOCULAR O: U+A66E
* combining O for Church Slavonic abbreviations (as трⷪца = троица '(Holy) Trinity'):
** COMBINING CYRILLIC LETTER O: 2DEA