A blister forms on a part of the body that is exposed to repeated friction or back and forth movement. Blisters form on hands and feet from repetitive work activity or from walking.
Joe has a blister on his heel because he walked five miles today.
One of the reasons for wearing socks on your feet is to avoid getting blisters.
Rachel has blisters on her fingers because she played the guitar for several hours last night.
It’s a good idea to wear gloves when raking leaves; otherwise, you might get blisters on your hands.
I’ve got blisters on my fingers!
The word "blistering" is sometimes used as an adverb or an adjective in place of "very."
It’s blistering hot outside today. (It’s very hot.)
A few people fainted in the blistering heat. (In this and the following sentences, "blistering" is an adjective.)
The runner broke yet another world record with his blistering speed on the track.
The construction project was completed with blistering speed.
The skin on her back is blistering from a sunburn. (In this sentence, "blistering" is a verb.)