[ hoh-moh-oo-see-uh n, -ou-, hom-oh- ]
/ ˌhoʊ moʊˈu si ən, -ˈaʊ-, ˌhɒm oʊ- /


a member of a 4th-century a.d. church party that maintained that the essence or substance of the Father and the Son is the same (opposed to Heteroousian).


of or relating to the Homoousians or their doctrine.

Origin of Homoousian

1555–65; < Late Greek homooúsi(os) of the same substance (Greek hom(o)- homo- + ousí(a) substance, essence + -os adj. suffix) + -an

Related forms

Ho·mo·ou·si·an·ism, noun
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British Dictionary definitions for homoousian


/ (ˌhəʊməʊˈuːsɪən, -ˈaʊ-, ˌhɒm-) /


a Christian who believes that the Son is of the same substance as the FatherCompare Homoiousian


of or relating to the Homoousians

Derived Forms

Homoousianism, noun

Word Origin for Homoousian

C16: from Late Greek homoousios of the same substance, from Greek homo- + ousia nature
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012