noun
1. common North American weed with linear leaves and small discoid heads of yellowish flowers
widely naturalized throughout temperate regions
sometimes placed in genus Erigeron
Synonym: Canadian fleabane fleabane Conyza canadensis Erigeron canadensis
2. erect perennial strong-scented with serrate pointed leaves and a loose panicle of yellowish flowers
the eastern United States
Synonym: horse balm stoneroot stone-root richweed stone root Collinsonia canadensis