[wohd] 
| 1. | a European plant, Isatis tinctoria, of the mustard family, formerly cultivated for a blue dye extracted from its leaves. |
| 2. | the dye extracted from this plant. |
| woad (wōd) n.
[Middle English wode, from Old English wād.] |
woad
(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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