Madder \Mad"der\, n. [OE. mader, AS. m[ae]dere; akin to Icel. ma?ra.]

(Bot.) A plant of the Rubia (R. tinctorum). The root is much used in dyeing red, and formerly was used in medicine. It is cultivated in France and Holland. See Rubiaceous.

Note: Madder is sometimes used in forming pigments, as lakes, etc., which receive their names from their colors; as. madder yellow.

Field madder, an annual European weed (Sherardia arvensis) resembling madder.

Indian madder, the East Indian Rubia cordifolia, used in the East for dyeing; -- called also munjeet.

Wild madder, Rubia peregrina of Europe; also the Galium Mollugo, a kind of bedstraw.

Source: Webster's Revised Unabridged Dictionary (1913)