1. a small, membranous cavity, sac, or cyst; specif.,
a. Anatomy and Medicine a small cavity or sac filled with fluid; esp., a small, round elevation of the skin containing a serous fluid; blister
b. Botany a small, bladderlike sac filled with air or liquid
Webster’s New World College Dictionary, Fourth Edition, compiled by the
editors of Webster’s New World Dictionaries. Copyright © 2010 by Houghton
Mifflin Harcourt. Published by Houghton Mifflin Harcourt. All rights reserved.
Word origin of 'vesicle'< Fr or L: Fr vésicule < L vesicula, dim. of vesica, bladder