woad, n. [OE. wod, AS. wād; akin to D. weede, G. waid, OHG. weit, Dan. vaid, veid, Sw. veide, L. vitrum.].
Wild woad (Bot.), the weld (Reseda luteola). See Weld. -- Woad mill, a mill grinding and preparing woad.
An herbaceous cruciferous plant (Isatis tinctoria
) of the family Cruciferae
). It was formerly cultivated for the blue coloring matter derived from its leaves. See isatin
. [1913 Webster
A blue dyestuff, or coloring matter, consisting of the powdered and fermented leaves of the Isatis tinctoria
. It is now superseded by indigo, but is somewhat used with indigo as a ferment in dyeing. [1913 Webster
"Their bodies . . . painted with woad in sundry figures."