"sumation" is probably misspelled. Trying summation instead Definition of summation
summation has definitions from the fields of mathematics,writing,biology
1
[ noun ] (writing) a concluding summary (as in presenting a case before a law court)

Synonyms

rundown summing_up

2
[ noun ] (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
[ noun ] the final aggregate

Synonyms

sum sum_total

Examples

"the sum of all our troubles did not equal the misery they suffered"

4
[ noun ] (mathematics) the arithmetic operation of summing; calculating the sum of two or more numbers

Synonyms

plus addition

Examples

"the summation of four and three gives seven" "four plus three equals seven"

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