- 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
WordReference Random House Learner's Dictionary of American English © 2017
- Plant Biology[countable] a plant of Europe having clusters of small yellowish flowers.
- Plant Biology[uncountable] the root of this plant, once used in dyeing.
- [uncountable] a dye derived from madder.
- Plant Biologyany plant of the genus Rubia, esp. the climbing R. tinctorum, of Europe, having open clusters of small, yellowish flowers. Cf. madder family.
- Plant Biologythe root of this plant, formerly used in dyeing.
- Textilesthe dye or coloring matter itself.
- Textilesa color produced by such a dye.
- bef. 1000; Middle English mad(d)er, Old English mæd(e)re; cognate with Old Norse mathra, Old High German matara
mad•der2 (mad′ər),USA pronunciation adj.
- comparative of mad.