orpiment Meaning, Definition & Usage

  1. noun a yellow mineral occurring in conjunction with realgar; an ore of arsenic

WordNet

Or"pi*ment noun
Etymology
F., fr. L. auripigmentum; aurum gold + pigmentum pigment. Cf. Aureate, Pigment, Orpin, Orpine.
Definitions
  1. (Chem.) 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.

Webster 1913