/ Dictionary / Index S somniferous: Meaning and Definition of Find definitions for: som•nif•er•ous Pronunciation: (som-nif'ur-us, sum-), [key] — adj. bringing or inducing sleep, as drugs or influences. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. See also: somniferous (Thesaurus) somnifacient somnific Related Content Daily Word Quiz: stringent Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language