What is it, then?
Science isn't the "ultimate truth". Science proposes theories and models that explain the observed behaviour of a system. But those theories and models are just that; theories and models. You cannot find "truth" with science. Just think about what science was a couple of centuries ago: the earth is flat, there are only four elements, irrational numbers don't exist... the list goes on and on.
In a way, one could even say that religion is "science". After all, religion gives explanations to observations (it is raining
because God is angry)