A vesicle, or blister, is a thin-walled sac filled with a fluid, usually clear and small. Vesicle is an important term used to describe the appearance of many rashes that typically consist of or begin with tiny-to-small fluid-filled blisters.
Update Date 5/13/2011
Updated by: Kevin Berman, MD, PhD, Atlanta Center for Dermatologic Disease, Atlanta, GA. Review provided by VeriMed Healthcare Network. Also reviewed by David Zieve, MD, MHA, Medical Director, A.D.A.M., Inc.