blister

Concise Oxford English Dictionary © 2008 Oxford University Press:
blister/ˈblɪstə(r)/

▶noun

• 1 a small bubble on the skin filled with serum and typically caused by friction or burning.

• 2 a similar swelling, filled with air or fluid, on a surface.

• 3 Medicine, chiefly historical a preparation applied to the skin to form a blister.

• 4 Brit. informal, dated an annoying person.

▶verb be or cause to be affected with blisters.

– origin ME: perh. from OFr. blestre ‘swelling, pimple’.