/ Dictionary / Index S Sergius III: Meaning and Definition of Find definitions for: Sergius III Pronunciation: [key] dieda.d.911, pope 904–911. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. Sergius II Sergius IV Related Content Daily Word Quiz: perspicacious Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language