cudweed \ˈ ̷ ̷ˌ ̷ ̷\noun : any of several composite plants with silky or woolly foliage: as a.: a European perennial herb (Gnaphalium sylvaticum) sometimes cultivated and widely naturalized as an escape in temperate No. America; broadly: any plant of the genus Gnaphalium b.: ladies' tobacco c.: cotton rose 2 d.: wormwood 1