Emily Dickinson Lexicon

HO-MO-OU'SIAN, or HO-MOI-OU'SIAN, a. [Gr. ομοουσιος, the same; ομος, similar, and ουσια, being: ομοιουσιος; ομοιος, similar, and ουσια.]

These terms were formerly used by the orthodox and Arian parties, to distinguish those who believed the Father and the Son to be of the same nature, from those who believed them to be of a similar nature. The words may be used as adjectives or nouns.. [1844 Addenda.]