CHURCH SLAVONIC
Church Slavonic: translation
Liturgical language of many Eastern Christian Orthodox Churches (e.g., Russian). Slavic peoples who accepted Christianity from Byzantine missionaries translated the liturgies into Old Slavonic, using an alphabet dating from the ninth century attributed to St. Cyril of Thessalonika. In the 10th century, a new alphabet (Cyrillic) appeared in Bulgaria. After the 11th century, the written liturgical language became known as Church Slavonic (also known as Old Bulgarian), of which there may be variants in the liturgies of national churches.
See also Glagolitic Mass.