a bluish discoloration of the skin caused by lack of oxygen, cold exposure, drug use



Image includes blue genipa stained hands, frozen airless moons, floating hydra
(hydralazine toxicity can cause cyanosis)

http://en.wikipedia.org/wiki/Cyanosis
http://en.wikipedia.org/wiki/Genipa_americana
http://en.wikipedia.org/wiki/Hydralazine