Source : Webster's Revised Unabridged Dictionary (1913)

Macrocosm \Mac"ro*cosm\, n. [Macro- + Gr. ? the world: cf. F.
   macrocosme.]
   The great world; that part of the universe which is exterior
   to man; -- contrasted with microcosm, or man. See
   {Microcosm}.

Source : WordNet®

macrocosm
     n : everything that exists anywhere; "they study the evolution
         of the universe"; "the biggest tree in existence" [syn: {universe},
          {existence}, {creation}, {world}, {cosmos}]