/ Thesaurus / R Synonyms of river dolphin Find synonyms for: Noun1. river dolphin, dolphinusage: any of several long-snouted usually freshwater dolphins of South America and southern AsiaWordNet 3.0 Copyright © 2006 by Princeton University. All rights reserved. Related Content Daily Word Quiz: abominable Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language