The Collaborative International Dictionary of English v.0.48:

Cold \Cold\, n.
   1. The relative absence of heat or warmth.
      [1913 Webster]

   2. The sensation produced by the escape of heat; chilliness
      or chillness.
      [1913 Webster]

            When she saw her lord prepared to part,
            A deadly cold ran shivering to her heart. --Dryden.
      [1913 Webster]

   3. (Med.) A morbid state of the animal system produced by
      exposure to cold or dampness; a catarrh.
      [1913 Webster]

   Cold sore (Med.), a vesicular eruption appearing about the
      mouth as the result of a cold, or in the course of any
      disease attended with fever.

   To leave one out in the cold, to overlook or neglect him.
      [Colloq.]
      [1913 Webster]

WordNet (r) 3.0 (2006):

cold sore
    n 1: caused by herpes simplex virus type 1 (HSV-1) [syn: oral
         herpes, herpes labialis, cold sore, fever blister]