Source : Webster's Revised Unabridged Dictionary (1913)

Summation \Sum*ma"tion\, n. [Cf. F. sommation. See {Sum}, v. t.]
   The act of summing, or forming a sum, or total amount; also,
   an aggregate.

         Of this series no summation is possible to a finite
         intellect.                               --De Quincey.

Source : WordNet®

summation
     n 1: a concluding summary (as in presenting a case before a law
          court) [syn: {summing up}, {rundown}]
     2: (physiology) the process whereby multiple stimuli can
        produce a response (in a muscle or nerve or other part)
        that one stimulus alone does not produce
     3: the final aggregate; "the sum of all our troubles did not
        equal the misery they suffered" [syn: {sum}, {sum total}]
     4: the arithmetic operation of summing; calculating the sum of
        two or more numbers; "the summation of four and three
        gives seven"; "four plus three equals seven" [syn: {addition},
         {plus}]