Noun
A reddish brown amorphous dyestuff, /, obtained from orcin, and forming the essential coloring matter of cudbear and archil. It is closely related to litmus.
Source: Webster's dictionaryOrcein began to achieve popularity again in the 19th century, when violet and purple became the color of demi-mourning, worn after a widow or widower had worn black for a certain time, before he or she returned to wearing ordinary colors. Source: Internet