/ Dictionary / Index T Trinitarianism: Meaning and Definition of Find definitions for: Trin•i•tar•i•an•ism Pronunciation: (trin"i-târ'ē-u-niz"um), [key] — n. the belief in, or doctrine of, the Trinity. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. See also: trinitarianism (Thesaurus) Trinitarian trinitro- Related Content Daily Word Quiz: spectral Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language