The Collaborative International Dictionary of English v.0.48:

Semitic \Sem*it"ic\, a.
   Of or pertaining to Shem or his descendants; belonging to
   that division of the Caucasian race which includes the Arabs,
   Jews, and related races. [Written also Shemitic.]
   [1913 Webster]

   Semitic language, a name used to designate a group of
      Asiatic and African languages, some living and some dead,
      namely: Hebrew and Ph[oe]nician, Aramaic, Assyrian,
      Arabic, Ethiopic (Geez and Ampharic). --Encyc. Brit.
      [1913 Webster]

WordNet (r) 3.0 (2006):

Semitic
    adj 1: of or relating to the group of Semitic languages;
           "Semitic tongues have a complicated morphology"
    2: of or relating to or characteristic of Semites; "Semite
       peoples" [syn: Semite, Semitic]
    n 1: a major branch of the Afro-Asiatic language family