Yery

Slavic letters
А Б В Г Ґ Д Ђ Ѓ Е Ѐ Ё Є Ж З Ѕ И Ѝ І Ї Й Ј К Л Љ М Н Њ О П Р С Т Ћ Ќ У Ў Ф Х Ц Ч Џ Ш Щ Ъ Ы Ь Э Ю Я
Non-Slavic letters
Ӑ А̄ А̊ А̃ Ӓ Ӓ̄ Ә Ә́ Ә̃ Ӛ Ӕ Ғ Г̧ Г̑ Г̄ Ҕ Ӻ Ӷ Ԁ Ԃ Ꚃ Ꚁ Ꚉ Ԫ Ԭ С́ Ӗ Е̄ Е̃ Ё̄ Є̈ Ӂ Җ Ꚅ Ӝ Ԅ Ҙ Ӟ З́ Ԑ Ԑ̈ Ӡ Ԇ Ӣ И̃ Ҋ Ӥ Қ Ӄ Ҡ Ҟ Ҝ Ԟ Ԛ Ӆ Ԯ Ԓ Ԡ Ԉ Ԕ Ӎ Ӊ Ң Ԩ Ӈ Ҥ Ԣ Ԋ О̆ О̃ О̄ Ӧ Ө Ө̄ Ӫ Ҩ Ԥ Ҧ Р̌ Ҏ Ԗ Ҫ Ԍ Ꚑ Ҭ Ꚋ Ꚍ Ԏ У̃ Ӯ Ӱ Ӱ́ Ӳ Ү Ү́ Ұ Х̑ Ҳ Ӽ Ӿ Һ Һ̈ Ԧ Ꚕ Ҵ Ꚏ Ҷ Ӵ Ӌ Ҹ Ꚓ Ꚗ Ꚇ Ҽ Ҿ Ы̆ Ы̄ Ӹ Ҍ Э̆ Э̄ Э̇ Ӭ Ӭ́ Ӭ̄ Ю̆ Ю̈ Ю̈́ Ю̄ Я̆ Я̄ Я̈ Ԙ Ԝ Ӏ
Archaic letters
Ꙁ Ꙃ Ꙅ Ꙇ Ꙉ Ҁ Ѻ ОУ Ꙋ Ѡ Ѽ Ꙍ Ѿ Ꙏ Ѣ Ꙑ Ꙓ Ꙕ Ꙗ Ѥ Ѧ Ꙙ Ѫ Ꙛ Ѩ Ꙝ Ѭ Ѯ Ѱ Ѳ Ѵ Ѷ Ꙟ Ꙡ Ꙣ Ꙥ Ꙧ Ꙩ Ꙫ Ꙭ ꙮ Ꚙ Ꚛ
List of Cyrillic letters Cyrillic digraphs

Yery, Yeru, Ery or Eru (Ы, ы, usually called "Ы" [ɨ] in modern Russian or "еры" yerý historically and in modern Church Slavonic) is a letter in the Cyrillic script. It represents the phoneme /i/ after non-palatalised (hard) consonants in the Belarusian and Russian alphabets.

Because of phonological processes, the actual realisation of /i/ after alveolar consonants (⟨д⟩, ⟨з⟩, ⟨л⟩, ⟨н⟩, ⟨р⟩, ⟨с⟩, ⟨т⟩, or ⟨ц⟩) is retracted to a close central unrounded vowel [ɨ] or [ʷi], after labials: ⟨б⟩, ⟨в⟩, ⟨м⟩, ⟨п⟩.

In Rusyn, it denotes a sound a bit harder than [ɨ] and close to the Romanian sound î, also written â. In some situations, it may occur after palatalised consonants (синьый "blue", which never happens in Russian), and it often follows ⟨к⟩, ⟨г⟩, ⟨ґ⟩ and ⟨х⟩.

While vowel letters in the Cyrillic alphabet may be divided into iotated and non-iotated pairs (for example, ⟨а⟩ and ⟨я⟩ both represent /a/, the latter denoting a preceding palatalised consonant), ⟨ы⟩ is more complicated. It appears only after hard consonants, its phonetic value differs from ⟨и⟩, and there is some scholarly disagreement as to whether or not ⟨ы⟩ and ⟨и⟩ denote different phonemes.

Like many other Cyrillic letters, it was originally from a ligature: ꙑ, formed from Yer ⟨ъ⟩ and ⟨і⟩ (formerly written either dotless or with two dots) or Izhe (⟨и⟩ which formerly resembled ⟨н⟩). In mediaeval manuscripts, it is almost always found as ⟨ъі⟩ or ⟨ъи⟩. Once the letters ⟨ъ⟩ and ⟨ь⟩ later lost their values as vowels in the Slavic languages, the current simplified form ⟨ы⟩ evolved.

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Wikipedia