• (a.) Having different essential qualities; of a different nature. • (n.) One of those Arians who held that the Son was of a different substance from the Father.
Het`er·o·ou'si·an noun (Eccl. Hist.) One of those Arians who held that the Son was of a different substance from the Father. Het`er·o·ou`si·an adjective [ Hetero- + Greek ... being, essence.] Having different essential qualities; of a different nature.