/ Dictionary / Index B brontosaurus: Meaning and Definition of Find definitions for: bron•to•sau•rus Pronunciation: (bron"tu-sôr'us), [key] — pl. -sau•rus•es, -sau•ri brontosaur. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. See also: brontosaurus (Thesaurus) brontosaur Bronx Related Content Daily Word Quiz: secular Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language