a polypeptide, CHONS, containing cysteine, glutamic acid, and glycine and involved, as an antioxidant and coenzyme, in the normal biochemical reactions occurring in plant and animal tissues
See glutathione in American Heritage Dictionary 4
noun
A polypeptide, C10H17N3O6S, of glycine, cysteine, and glutamic acid that occurs widely in plant and animal tissues and is important in biological oxidation-reduction reactions.