Noun
1. a quantity of money;
"he borrowed a large sum""the amount he had in cash was insufficient"2. a quantity obtained by addition
3. the final aggregate;
"the sum of all our troubles did not equal the misery they suffered"4. the choicest or most essential or most vital part of some idea or experience;
"the gist of the prosecutor's argument""the heart and soul of the Republican Party""the nub of the story"5. the whole amount
6. the basic unit of money in Uzbekistan
7. a set containing all and only the members of two or more given sets;
"let C be the union of the sets A and B"