Source : Webster's Revised Unabridged Dictionary (1913)

Murexide \Mu*rex"ide\, n. [L. murex the purple fish, purple.]
   (Chem.)
   A crystalline nitrogenous substance having a splendid
   dichroism, being green by reflected light and garnet-red by
   transmitted light. It was formerly used in dyeing calico, and
   was obtained in a large quantities from guano. Formerly
   called also {ammonium purpurate}.