The Cyrillic script (pronounced /sɨˈrɪlɪk/, Bulgarian: Кирилица [kɨˈrɪlɪtsa], Russian: Кири́ллица [kʲɪˈrʲilʲɪʦə]) is an alphabet developed in the 9th century in Bulgaria, and used in the Slavic national languages of Belarusian, Bosnian, Bulgarian, Russian, Rusyn, Serbian, Macedonian, Montenegrin and Ukrainian, and in the non-Slavic languages of Moldovan, Kazakh, Uzbek, Kyrgyz, Tajik, Tuvan, and Mongolian. It also was used in past languages of Eastern Europe, the Caucasus, and Siberia.
The Cyrillic alphabet is also known as azbuka, derived from the old names of the first two letters of most variant Cyrillic alphabets. With the accession of Bulgaria to the European Union on 1 January 2007, Cyrillic became the third official alphabet of the European Union, following the Latin and Greek alphabets.
Cyrillic is one of the two alphabets (together with Glagolitic) used in the Church Slavonic language, especially the Old Church Slavonic variant (see Early Cyrillic alphabet). Hence, expressions such as “И is the tenth letter of the Cyrillic alphabet” typically denote that meaning; moreover, not every Cyrillic-based language uses every letter of the alphabet.
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