Blisters
Also called: Bulla, Vesicle
Summary
What are blisters?
Blisters are fluid-filled sacs on the outer layer of your skin. They form because of rubbing, heat, or diseases of the skin. They are most common on your hands and feet.
Other names for blisters are vesicles (usually for smaller blisters) and bulla (for larger blisters).
https://medlineplus.gov/blisters.html
