- any plant of the genus Rubia, especially the climbing R. tinctorum, of Europe, having open clusters of small, yellowish flowers.
- the root of this plant, formerly used in dyeing.
- the dye or coloring matter itself.
- a color produced by such a dye.
- comparative of mad.
- any of several rubiaceous plants of the genus Rubia, esp the Eurasian R. tinctoria, which has small yellow flowers and a red fleshy root
- the root of this plant
- a dark reddish-purple dye formerly obtained by fermentation of this root; identical to the synthetic dye, alizarin
- a red lake obtained from alizarin and an inorganic base; used as a pigment in inks and paints
- the comparative of mad
