/ Thesaurus / P Synonyms of parthenium Find synonyms for: Noun1. Parthenium, genus Parthenium, asterid dicot genususage: small genus of North American herbs and shrubs with terminal panicles of small ray flowersWordNet 3.0 Copyright © 2006 by Princeton University. All rights reserved. Related Content Daily Word Quiz: reticent Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language