herpes simplex
    n 1: an infection caused by the herpes simplex virus; affects
         the skin and nervous system; produces small temporary (but
         sometimes painful) blisters on the skin and mucous
         membranes
    2: a herpes virus that affects the skin and nervous system [syn:
       herpes simplex, herpes simplex virus]

Herpes simplex \Her"pes simp`lex\, n. (Med.)
   either of two forms of herpesvirus infection, distinguished
   as being caused by herpes simplex virus type 1 (HSV-1), which
   causes mostly sores and eruptions around the mouth (cold
   sores and fever blisters) and at other points above the
   waist, and herpes simplex virus type 2 (HSV-2), causing
   genital herpes. HSV-1 is also known in some cases to cause
   genital herpes infections.
   [PJC]