Consubstantial

Consubstantial a word of similar import with co-essential, denoting something of the same substance with another. The term ὁμοούσιος was first used by the fathers of the councils of Antioch and Nicaea to express the orthodox doctrine more precisely. At first the term had only a negative use, as against the Arian heresy; but after the adoption of the Nicene Creed it became a test- word of orthodoxy. — Tomline, Theology, 2:110; Schaff, History of the Christian Church, § 127.