Nestorian is a term that refers to a Christian sect that existed in the 5th century. The Nestorians were known for their belief in the duality of Christ, which meant that they believed that Jesus had two distinct natures, one human and one divine. However, the term Nestorian is outdated and is rarely used today. Instead, other terms are used to describe this sect, such as the Church of the East or the Assyrian Church. These synonyms are more appropriate and accurate, and they reflect the modern understanding of the history and theology of this Christian group.