cold sore

/ˈkoʊld ˌsɔɹ/

cold sore

English Noun

Definition

A small bump (namely a vesicle) on the lips resulting from infection by herpes simplex viruses (mostly HHV1 but also HHV2).

Etymology

Compound of cold + sore, probably for the tendency of the vesicles to recur along with other illness, or possibly during cold weather, though this explanation is less common. Compare synonym fever blister.