Definition of stoma

• n. - One of the minute apertures between the cells in many serous membranes.
• n. - The minute breathing pores of leaves or other organs opening into the intercellular spaces, and usually bordered by two contractile cells.
• n. - The line of dehiscence of the sporangium of a fern. It is usually marked by two transversely elongated cells. See Illust. of Sporangium.
• n. - A stigma. See Stigma, n., 6 (a) & (b).