haemacyanin

Hæm`a*cy"a*nin, n. Etym: [Hæma- + Gr. (Physiol. Chem.) Defn: A substance found in the blood of the octopus, which gives to it its blue color. Note: When deprived of oxygen it is colorless, but becomes quickly blue in contact with oxygen, and is then generally called oxyhæmacyanin. A similar blue coloring matter has been detected in small quantity in the blood of other animals and in the bile.

---