Source : Webster's Revised Unabridged Dictionary (1913)

Visitor \Vis"it*or\ [Cf. F. visiteur.] [Written also {visiter}.]
   1. One who visits; one who comes or goes to see another, as
      in civility or friendship. ``This great flood of
      visitors.'' --Shak.

   2. A superior, or a person lawfully appointed for the
      purpose, who makes formal visits of inspection to a
      corporation or an institution. See {Visit}, v. t., 2, and
      {Visitation}, n., 2.

            The king is the visitor of all lay corporations.
                                                  --Blackstone.

Source : WordNet®

visitor
     n : someone who visits [syn: {visitant}]