/ Thesaurus / O Synonyms of ohio river Find synonyms for: Noun1. Ohio, Ohio Riverusage: a river that is formed in western Pennsylvania and flows westward to become a tributary of the Mississippi RiverWordNet 3.0 Copyright © 2006 by Princeton University. All rights reserved. Related Content Daily Word Quiz: ontiguous Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language