Source : Webster's Revised Unabridged Dictionary (1913)

Cooperation \Co*["o]p`er*a"tion\, n. [L. co["o]peratio: cf. F.
   coop['e]ration.]
   1. The act of co["o]perating, or of operating together to one
      end; joint operation; concurrent effort or labor.

            Not holpen by the co["o]peration of angels. --Bacon.

   2. (Polit. Econ.) The association of a number of persons for
      their benefit.

Source : WordNet®

cooperation
     n 1: joint operation or action; "their cooperation with us was
          essential for the success of our mission" [ant: {competition}]
     2: the practice of cooperating; "economic cooperation"; "they
        agreed on a policy of cooperation"