stroma

stroma /strō″mə/ pl. stromas, stromata [Gk, covering] , the supporting tissue or the matrix of an organ, as distinguished from its parenchyma. Some kinds of stromata are the vitreous stroma, which encloses the vitreous humor of the eye, and Rollet’s stroma, which contains the hemoglobin of a red blood cell. −stromatic, adj.