\Cud"bear`\ (k?d"b?r`), n. [Also {cudbeard}, corrupted
fr. the name of Dr. Cuthbert Gordon, a Scotchman, who first
brought it into notice.]
1. A powder of a violet red color, difficult to moisten with
   water, used for making violet or purple dye. It is
   prepared from certain species of lichen, especially
   {Lecanora tartarea}. --Ure.
2. (Bot.) A lichen ({Lecanora tartarea}), from which the
   powder is obtained.