Vesicle
Vesicle , noun
[Latin vesicula, dim. of vesica a bladder, blister; akin to Sanskrit vasti bladder: compare French vésicule.]
A bladderlike vessel; a membranous cavity; a cyst; a cell.
(a)
(Botany) A small bladderlike body in the substance of a vegetable, or upon the surface of a leaf.
(b)
(Medicine) A small, and more or less circular, elevation of the cuticle, containing a clear watery fluid.
(c)
(Anatomy) A cavity or sac, especially one filled with fluid; as, the umbilical vesicle.
(d)
(Zoology) A small convex hollow prominence on the surface of a shell or a coral.
(e)
(Geology) 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.