NonChalcedonian

NonChalcedonian refers to Christian churches that rejected the Council of Chalcedon (451) and the definition of Christ's two natures in one person. In scholarly and ecumenical usage, the term describes communities that adhere to Miaphysite Christology, which holds that Christ has one united nature, divine and human. The label is used to distinguish these churches from Chalcedonian churches that accepted the Chalcedonian Definition.

Historically, the Chalcedonian schism led to the formation of the Oriental Orthodox communion, a family of churches that preserve diverse liturgical traditions while sharing a common Christological framework. NonChalcedonian churches are often categorized within Oriental Orthodoxy in modern classifications.

Major members include the Coptic Orthodox Church of Alexandria; Syriac Orthodox Church; Armenian Apostolic Church; Ethiopian Orthodox Tewahedo Church; Eritrean Orthodox Tewahedo Church; and the Malankara Orthodox Syrian Church (Indian Orthodox Church). These churches maintain ancient liturgies and ecclesiastical structures rooted in communities across Egypt, Syria, Armenia, Ethiopia, Eritrea, and India.

Terminology note: While the term NonChalcedonian is common in academic discussions, many of these churches prefer to be described as Oriental Orthodox or Miaphysite rather than with the label NonChalcedonian. The distinction remains a central point in historical and contemporary Christian doctrinal dialogues.