sum

1 :  an indefinite or specified amount of money

2 :  the whole amount :  aggregate

3 :  the utmost degree :  summit reached the sum of human happiness

4a :  a summary of the chief points or thoughts :  summation the sum of this criticism follows — C. W. Hendelb :  gist the sum and substance of an argument

5a (1) :  the result of adding numbers the sum of 5 and 7 is 12 (2) :  the limit of the sum of the first n terms of an infinite series as n increases indefinitelyb :  numbers to be added; broadly :  a problem in arithmeticc (1) :  disjunction 2 (2) :  union 2d