Theotokos

Theotokos (Koine Greek: Θεοτόκος) is a title of Mary, mother of Jesus, used especially in Eastern Christianity. The usual Latin translations are Dei Genitrix or Deipara (approximately "parent [fem] of God"). Common English translations are "Mother of God" or "God-bearer" – but these both have different literal equivalents in Ancient Greek: Μήτηρ Θεοῦ, and Θεοφόρος respectively.

The title has been in use since the 3rd century, and in the Liturgy of Saint James (4th century). The Council of Ephesus in AD 431 decreed that Mary is the Theotokos because her son Jesus is both God and man: one divine person from two natures (divine and human) intimately and hypostatically united.

The title of Mother of God (Ancient Greek: Μήτηρ (τοῦ) Θεοῦ) or Mother of Incarnate God, abbreviated ΜΡ ΘΥ (the first and last letter of main two words in Greek), is most often used in English, largely due to the lack of a satisfactory equivalent of the Greek τόκος. For the same reason, the title is often left untranslated, as Theotókos, in Eastern liturgical usage of other languages.

Theotokos is also used as the term for an Eastern icon, or type of icon, of the Mother with Child (typically called a Madonna in the Western tradition), as in "the Theotokos of Vladimir" both for the original 12th-century icon and for icons that are copies or imitate its composition.