n. bladder or bladder-like cavity; small blister filled with fluid; sac in the body, cyst (especially one filled with fluid); cavity formed in a rock by a pocket of gas that is trapped during the rock's formation (Geology)
VESICLE
Meaning of VESICLE in English
Explanatory English dictionary bed edition. Толковый словарь английского языка Редакция bed. 2012