The Collaborative International Dictionary of English v.0.48:

Guadalcanal \Guadalcanal\ n.
   1. a mountainous island; the largest of the Solomon Islands
      in the independent state that is a member of the British
      Commonwealth.
      [WordNet 1.5]

   2. A battle in World War II in the Pacific (1942-1943), in
      which American forces invaded the island of Guadalcanal,
      then occupied by Japanese forces; the island was
      recaptured by American forces after heavy fighting.

   Syn: battle of Guadalcanal.
        [WordNet 1.5]

WordNet (r) 3.0 (2006):

Guadalcanal
    n 1: a mountainous island; the largest of the Solomon Islands in
         the independent state that is a member of the British
         Commonwealth
    2: a battle in World War II in the Pacific (1942-1943); the
       island was occupied by the Japanese and later recaptured by
       American forces [syn: Guadalcanal, Battle of Guadalcanal]