Definition: Subtraction tells "how many are left" or "how many more or less."

Subtraction is removing some objects from a group. The meaning of 5-3=2 is "Three objects are taken away from a group of five objects and two objects remain".

8 - 3 = 5
eight minus three equals five
        difference

Subtraction  is not commutative. When the order of the numbers in a subtraction problem are changed, the answer is different. For example 8 – 5 is not the same difference as 5 - 8.