Source : Webster's Revised Unabridged Dictionary (1913)

Commemoration \Com*mem`o*ra"tion\, n. [L. commemoratio.]
   1. The act of commemorating; an observance or celebration
      designed to honor the memory of some person or event.

            This sacrament was designed to be a standing
            commemoration of the death and passion of our Lord.
                                                  --Abp.
                                                  Tillotson.

            The commonwealth which . . . chooses the most
            flagrant act of murderous regicide treason for a
            feast of eternal commemoration.       --Burke.

   2. Whatever serves the purpose of commemorating; a memorial.

   {Commemoration day}, at the University of Oxford, Eng., an
      annual observance or ceremony in honor of the benefactors
      of the University, at which time honorary degrees are
      conferred.

Source : WordNet®

commemoration
     n 1: a ceremony to honor the memory of someone or something [syn:
           {memorialization}, {memorialisation}]
     2: a recognition of meritorious service [syn: {memorial}, {remembrance}]