/ Dictionary / Index D Decius: Meaning and Definition of Find definitions for: De•cius Pronunciation: (dē'shus, desh'us), [key] — n. a.d. c201–251, emperor of Rome 249–251. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. See also: decius (Thesaurus) decisive deck Related Content Daily Word Quiz: reclusive Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language