Source : Webster's Revised Unabridged Dictionary (1913)

Salutation \Sal`u*ta"tion\, n. [L. salutatio: cf. F. salutation.
   See {Salute}.]
   The act of saluting, or paying respect or reverence, by the
   customary words or actions; the act of greeting, or
   expressing good will or courtesy; also, that which is uttered
   or done in saluting or greeting.

         In all public meetings or private addresses, use those
         forms of salutation, reverence, and decency usual
         amongst the most sober persons.          --Jer. Taylor.

   Syn: Greeting; salute; address.

   Usage: {Salutation}, {Greeting}, {Salute}. Greeting is the
          general word for all manner of expressions of
          recognition, agreeable or otherwise, made when persons
          meet or communicate with each other. A greeting may be
          hearty and loving, chilling and offensive, or merely
          formal, as in the opening sentence of legal documents.
          Salutation more definitely implies a wishing well, and
          is used of expressions at parting as well as at
          meeting. It is used especially of uttered expressions
          of good will. Salute, while formerly and sometimes
          still in the sense of either greeting or salutation,
          is now used specifically to denote a conventional
          demonstration not expressed in words. The guests
          received a greeting which relieved their
          embarrassment, offered their salutations in
          well-chosen terms, and when they retired, as when they
          entered, made a deferential salute.

                Woe unto you, Pharisees! for ye love the
                uppermost seats in the synagogues, and greetings
                in the markets.                   --Luke xi. 43.

                When Elisabeth heard the salutation of Mary, the
                babe leaped in her womb.          --Luke i. 41.

                I shall not trouble my reader with the first
                salutes of our three friends.     --Addison.

Source : WordNet®

salutation
     n 1: an act of honor or courteous recognition; "a musical salute
          to the composer on his birthday" [syn: {salute}]
     2: (usually plural) an acknowledgment or expression of good
        will (especially on meeting) [syn: {greeting}]
     3: word of greeting used to begin a letter