Aquinas predated Popper, whose definition is more influential today. Nothing about theology is falsifiable, so no, the answer is "No."

Theology is a "science" in the same way as social science is a science. They don't use the scientific approach as defined by Popper, but they still try to find out stuff in the best possible way.

Specifically theology searches for knowledge by appealing to scripture and tradition as sources of fact, in the same way that modern science appeals to empirical observation. A theologian of Aquinas's time would have been confident that both methods of study would lead to the same conclusions.

It's certainly the case that the term "science" now refers strictly to empirical science.

Social scientists use the scientific method and a lot of statistics.