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An herbaceous cruciferous plant (Isatis tinctoria). It was formerly cultivated for the blue coloring matter derived from its leaves.

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 It is now superseded by indigo, but is somewhat used with indigo as a ferment in dyeing.

An herbaceous cruciferous plant (Isatis tinctoria). It was formerly cultivated for the blue coloring matter derived from its leaves.

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 It is now superseded by indigo, but is somewhat used with indigo as a ferment in dyeing.

A plant of the cabbage family yielding a blue dye; also, the dyestuff.

A plant used as a blue dye-stuff.

n. [Anglo-Saxon] An herbaceous plant of the genus Isatis, formerly cultivated for the blue colouring matter derived from ire leaves ;—the colouring matter, or the colour derived from the plant.