Added 9 October 2026 parthenium noun Categories: PlantsObscure Words noun ! Definition from WordNet 3.1, Princeton University. More about parthenium at Wordnik → Where our words come from → Small genus of North American herbs and shrubs with terminal panicles of small ray flowers. Origin From the genus name. From Wiktionary, via Kaikki.org (CC BY-SA) Related Words: argentatumparietaryperisteriaperigoniumpentanderperianthiumpentadelphyhippeastrumpterophytepetalumperianth Back to today's word