horseweed

Noun horseweed has 2 senses

• horseweed(n = noun.plant) collinsonia canadensis, horse balm, richweed, stone root, stone-root, stoneroot - erect perennial strong-scented with serrate pointed leaves and a loose panicle of yellowish flowers; the eastern United States;
is a kind of herb, herbaceous plant
is a member of collinsonia, genus collinsonia

• horseweed(n = noun.plant) canadian fleabane, conyza canadensis, erigeron canadensis, fleabane - common North American weed with linear leaves and small discoid heads of yellowish flowers; widely naturalized throughout temperate regions; sometimes placed in genus Erigeron;
is a member of conyza, genus conyza
is a kind of weed