| cold sore n. A small blister occurring on the lips and face and caused by herpes simplex. Also called fever blister, herpes labialis. |
herpes la·bi·a·lis (lā'bē-ā'lĭs) n. See cold sore. [New Latin herpēs labiālis : Latin herpēs, herpes + Medieval Latin labiālis, of the lip.] |