Definitions for "Ragweed"
A common American composite weed (Ambrosia artemisiæfolia) with finely divided leaves; hogweed.
widespread European weed having yellow daisylike flowers; sometimes an obnoxious weed and toxic to cattle if consumed in quantity
any of numerous chiefly North American weedy plants constituting the genus Ambrosia that produce highly allergenic pollen responsible for much hay fever and asthma