/ves"i keuhl/ , n.
1. a small sac or cyst.
2. Biol. a small bladderlike cavity, esp. one filled with fluid.
3. Pathol. a circumscribed elevation of the epidermis containing serous fluid; blister.
4. Geol. a small, usually spherical cavity in a rock or mineral, formed by expansion of a gas or vapor before the enclosing body solidified.
[ 1570-80; vesicula little bladder. See VESICA, -ULE ]