/ Thesaurus / P Synonyms of populus heterophylla Find synonyms for: Noun1. swamp cottonwood, black cottonwood, downy poplar, swamp poplar, Populus heterophylla, cottonwoodusage: North American poplar with large rounded scalloped leaves and brownish bark and woodWordNet 3.0 Copyright © 2006 by Princeton University. All rights reserved. Related Content Daily Word Quiz: cautious Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language