According to Merriam-Webster, the first number in a subtraction is called a minuend. The minuend is the number from which another number will be subtracted.
In essence, a subtraction goes "minuend - subtrahend = difference," where the subtrahend is the number being taken away from the minuend and the difference is what remains. In the equation:
- 9 - 6 = 3
Nine is the minuend, six is the subtrahend with the remainder (three) being the difference.
The word itself is Latin and is a gerundive of "minuere," meaning "to make smaller, lessen or diminish," though it can also be directly translated as "to let blood." The first known use of the word was in 1706.