Orpiment
Pronunciation : Or"pi*ment
Part of Speech : n.
Etymology : [F., fr. L. auripigmentum; aurum gold + pigmentum pigment. Cf. Aureate, Pigment, Orpin, Orpine.] (Chem.)
Definition : Defn: Arsenic sesquisulphide, produced artificially as an amorphous lemonyellow powder, and occurring naturally as a yellow crystalline mineral; -- formerly called auripigment. It is used in king's yellow, in white Indian fire, and in certain technical processes, as indigo printing. Our orpiment and sublimed mercurie. Chaucer. Red orpiment, realgar; the red sulphide of arsenic. -- Yellow orpiment, king's yellow.
Source : Webster's Unabridged Dictionary, 1913