Homoean, in the Trinitarian controversies of the 4th-century Christian Church, a follower of Acacius, bishop of Caesarea. The Homoeans taught a form of Arianism that asserted that the Son was distinct from, but like (Greek homoios), the Father, as opposed to the Nicene Creed, which stated that the Son is “of one substance” (Greek homoousios) with the Father.
The doctrine of the Homoeans was favoured by Emperor Constantius II, who called councils for the Western Church at Rimini (October 359) and for the Eastern Church at Seleucia (winter 359). Accepted for a time by the bishops of the entire Christian Church, the doctrine of the Homoeans was abandoned after Constantius’ death in 361. It was revived in the East during the reign of Emperor Valens (364–378) but was finally condemned, with all Arian views, at the first Council of Constantinople in 381.