stro·ma / ˈstrōmə/ • n. (pl. -ma·ta / -mətə/ ) 1. Anat. & Biol. the supportive tissue of an epithelial organ, tumor, gonad, etc., consisting of connective tissues and blood vessels. ∎  the spongy framework of protein fibers in a red blood cell or platelet. ∎  Bot. the matrix of a chloroplast, in which the grana are embedded.2. Bot. a cushionlike mass of fungal tissue, having spore-bearing structures either embedded in it or on its surface.DERIVATIVES: stro·mal adj. ( chiefly Anat. )stro·mat·ic / strōˈmatik/ adj. ( chiefly Bot. ).

stroma
1. A cushion-like mass of fungal tissue in or upon which spore-bearing structures may develop
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2. The matrix of chloroplasts, within which the grana (see GRANUM) are embedded. In addition to starch granules and oil droplets, it contains the enzymes responsible for the mediation of the dark reactions of photosynthesis.

stroma (stroh-mă) n. the connective-tissue basis of an organ, as opposed to the functional tissue (parenchyma). For example, the stroma of the erythrocytes is the spongy framework of protein strands within a red blood cell in which the blood pigment haemoglobin is packed; the stroma of the cornea is the transparent fibrous tissue making up the main body of the cornea.

stroma Tissue that forms the framework of an organ; for example, the tissue of the ovary that surrounds the reproductive cells, or the gel-like matrix of chloroplasts that surrounds the grana.

stroma (anat., etc.) framework of an organ or cell (as of connective tissue). XIX. — modL. use of late L. strōma mattress — Gr. strôma.