/ Thesaurus / C Synonyms of columbia river Find synonyms for: Noun1. Columbia, Columbia Riverusage: a North American river; rises in southwestern Canada and flows southward across Washington to form the border between Washington and Oregon before emptying into the Pacific; known for its salmon runs in the springWordNet 3.0 Copyright © 2006 by Princeton University. All rights reserved. Related Content Daily Word Quiz: denizen Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language