The Collaborative International Dictionary of English v.0.48:

Personality \Per`son*al"i*ty\, n.; pl. Personalities. [Cf. F.
   personnalit['e]. Cf. Personality.]
   1. That which constitutes distinction of person; the
      externally evident aspects of the character or behavior of
      a person; individuality.
      [1913 Webster +PJC]

            Personality is individuality existing in itself, but
            with a nature as a ground.            --Coleridge.
      [1913 Webster]

   2. Something said or written which refers to the person,
      conduct, etc., of some individual, especially something of
      a disparaging or offensive nature; personal remarks; as,
      indulgence in personalities.
      [1913 Webster]

            Sharp personalities were exchanged.   --Macaulay.
      [1913 Webster]

   3. (Law) That quality of a law which concerns the condition,
      state, and capacity of persons. --Burrill.
      [1913 Webster]

   4. A person who is famous or notable; a celebrity.
      [PJC]

WordNet (r) 3.0 (2006):

personality
    n 1: the complex of all the attributes--behavioral,
         temperamental, emotional and mental--that characterize a
         unique individual; "their different reactions reflected
         their very different personalities"; "it is his nature to
         help others"
    2: a person of considerable prominence; "she is a Hollywood
       personality"