/ Dictionary / Index S Seirios: Meaning and Definition of Find definitions for: Seir•i•os Pronunciation: (sir'ē-us), [key] — n. Class. Myth. Sirius (def. 2). Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. Seine-St-Denis seise Related Content Daily Word Quiz: neologism Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language