homoiousian
/ˌhɒmɔɪˈuːsɪən
/ /ˌhɒmɔɪˈaʊsɪən/ /ˌhɒmɔɪˈuːzɪən/ /ˌhɒmɔɪˈaʊzɪən/noun historical
A person who held that God the Father and God the Son are of like but not identical substance. Compare with homoousian.The arguments between the homoiousian and homoousians would be hysterically ridiculous if it weren't for the amount of blood shed over the letter ‘i’....
- Constantius at first supported these homoiousians but soon transferred his support to the homoousians, led by Acacius, who affirmed that the Son was ‘like’ the Father.
- In 381, the Council of Constantinople reaffirmed the credo of Nicaea and condemned the semi-Arians, the homoiousians.
Origin
Late 17th century (as an adjective in the sense 'of similar but not identical substance'): via ecclesiastical Latin from Greek homoiousios, from homoios 'like' + ousia 'essence, substance'. The noun dates from the mid 18th century.