mad·der 
(mădər)
(mădər)n.
1. Any of several plants of the genus Rubia, especially R. tinctorum of Eurasia, having small yellow flowers, whorled leaves, and a reddish-brown root.
2.
a. The root of R. tinctorum, formerly an important source of the dye alizarin.
b. A red dye obtained from these roots.
3. A medium to strong red or reddish orange.
[Middle English, from Old English mædere.]