Source : Webster's Revised Unabridged Dictionary (1913)

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.