For mathematical addition:
* Total: This is the most common synonym for the result of adding numbers.
* Aggregate: This implies combining multiple values into a single value.
* Summation: This is a more formal term used in mathematical contexts.
* Addition: While not strictly a synonym, this word refers to the process of adding.
For a summary:
* Summary: This is the most obvious synonym for a concise overview.
* Recap: This implies summarizing something that has already been discussed.
* Synopsis: This suggests a brief and comprehensive summary, often of a longer work.
* Abstract: This refers to a concise summary of a research paper.
For a collection or amount:
* Total: This can also refer to the entire amount of something.
* Amount: This is more general and refers to a quantity of something.
* Quantity: This is similar to "amount" but emphasizes the number rather than the specific thing.
Ultimately, the best synonym for "sum" will depend on the specific context and the nuance you want to convey.