1. [ noun ] (botany) widespread European weed having yellow daisylike flowers; sometimes an obnoxious weed and toxic to cattle if consumed in quantity
Synonyms: tansy_ragwort benweed Senecio_jacobaea ragwort
Related terms: weed Senecio
2. [ noun ] (botany) any of numerous chiefly North American weedy plants constituting the genus Ambrosia that produce highly allergenic pollen responsible for much hay fever and asthma
Synonyms: bitterweed ambrosia
Related terms: weed common_ragweed western_ragweed great_ragweed genus_Ambrosia
Similar spelling:   ragged