The Collaborative International Dictionary of English v.0.48:

Phycocyanin \Phy`co*cy"a*nin\, Phycocyanine \Phy`co*cy"a*nine\,
   n. [Gr. fy^kos seaweed + E. cyanin.]
   A blue coloring matter found in certain algae.
   [1913 Webster] Phycoerythrin