In math, anything that's described as multiplicative has something to do with repeatedly adding a number to itself. A simple multiplicative problem to solve is 3 X 3.
Whenever you multiply one number by another, that's a multiplicative operation. Your math teacher might refer to multiplicative properties of certain numbers, too; "According to the multiplicative property of zero, no matter what number you multiply by zero, you'll always get an answer of zero." Multiplicative shares a Latin root with multiply, multiplex, which means "having many folds."