/ Dictionary / Index T Theodosian: Meaning and Definition of Find definitions for: The•o•do•sian Pronunciation: (thē"u-dō'shun, -shē-un), [key] — adj. of or pertaining to Theodosius I, who made Christianity the official state religion of the Roman Empire. of or pertaining to Theodosius II, who issued the earliest collection of the imperial laws Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. Theodosia Theodosius I Related Content Daily Word Quiz: abdicate Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language