|1.||dyer's-weed See also dyer's rocket a European plant, Isatis tinctoria, formerly cultivated for its leaves, which yield a blue dye: family Brassicaceae (crucifers)|
|2.||the dye obtained from this plant, used esp by the ancient Britons, as a body dye|
|[Old English wād; related to Old High German weit; Middle Dutch wēd, Latin vitrum]|
(Isatis tinctoria), biennial or perennial herb, in a genus of about 80 species in the mustard family (Brassicaceae), formerly grown as a source of the blue dye indigo and now sometimes cultivated for its small, four-petalled yellow flowers. It is a summer-flowering native of Eurasia, now naturalized in southeastern North America. Woad reaches 90 cm (3 feet) and produces clusters of dangling, winged, oval, single-seeded fruits. The hairy stem leaves have arrow-shaped bases; the long basal leaves are downy and lance shaped. The ground and dried leaves, when wetted and fermented, produce indigotin.
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