The Collaborative International Dictionary
cudbeard
Cudbear \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.]
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.(Bot.) A lichen ( Lecanora tartarea), from which the powder is obtained.