/ Dictionary / Index R Rio Negro: Meaning and Definition of Find definitions for: Ri•o Ne•gro Pronunciation: (rē'oo ne'groo), [key] Portuguese name of Rí•o Ne•gro Pronunciation: (rē'ō nā'grō Sp. rē'ô ne'grô), [key] Spanish name of Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. Río Muni Rion Strait Related Content Daily Word Quiz: philtrum Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language