| Noun | 1. | willowherb - a plant of the genus Epilobium having pink or yellow flowers and seeds with silky hairs herb, herbaceous plant - a plant lacking a permanent woody stem; many are flowering garden plants or potherbs; some having medicinal properties; some are pests Epilobium, genus Epilobium - large widely distributed genus of herbs and subshrubs of especially western North America and Arctic areas Epilobium angustifolium, fireweed, giant willowherb, rosebay willowherb, wickup - tall North American perennial with creeping rootstocks and narrow leaves and spikes of pinkish-purple flowers occurring in great abundance in burned-over areas or recent clearings; an important honey plant codlins-and-cream, Epilobium hirsutum, hairy willowherb - plant of Europe and Asia having purplish-red flowers and hairy stems and leaves; introduced into North America |