/ Thesaurus / W Synonyms of willamette river Find synonyms for: Noun1. Willamette, Willamette Riverusage: a river in western Oregon that flows north into the Columbia River near PortlandWordNet 3.0 Copyright © 2006 by Princeton University. All rights reserved. Related Content Daily Word Quiz: pundit Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language