The crossword solution for the term ADDITIONAL ANSWERS is SUMS, which is a four-letter word. It is an abbreviation of the mathematical term 'SUMMATION, ' which is the process of adding up a series of numbers or quantities. Sums are used to calculate the total of a set of numbers, and can also be used to find the difference between two numbers. In addition, sums can be used to determine the average of a set of numbers.