A small cavity, nearly spherical in form, and usually of the size of a pea or smaller, such as are common in some volcanic rocks. They are produced by the liberation of watery vapor in the molten mass.
In fistuliporine cystoporates, blisterlike, boxlike, or less commmonly tubelike element of extrazooidal vesicular tissue bounded by calcified walls and roof; space in vesicle presumably contained no soft tissue. (Boardman & Cheetham, 1983)
In fungi a bubble-like structure produced by a zoosporangium and in which the zoospores are released or are differentiated. In animals a blister; a small circumscribed swelling of the epidermis containing a clear fluid. In general a body constructed as a bladder; a small, rigid, thin-walled structure.
In cell biology, a vesicle is a relatively small and enclosed compartment, separated from the cytosol by at least one lipid bilayer. If there is only one lipid bilayer, they are called unilamellar vesicles; otherwise they are called multilamellar. Vesicles store, transport, or digest cellular products and waste.