Making gods not to exist "by definition"

     One atheist (at least one) has decided that it is not enough that there is no evidence for alleged supernatural beings. He is stating that any such being, if found, would be natural by definition and therefore not a god. Quite frankly, I think that this is worse than useless. It gives validity to the common christian claim that non-believers are "closed to the evidence." I am open to actual evidence in favor of their god. I just haven't seen any. If I ever do see such evidence, I will not play games stating that "the multiverse or anything outside the world we can see is just natural anyway." The natural embodies the world that we currently see. And there might be an outside of that. By standard definitions, any such outside would be supernatural or at least extranatrual. The term "natural" was not intended to mean "everything that exists" and should not be so redefined. It may happen that it, in fact, encompasses everything that exists. But if it does, it will not be by virtue of saying "found it, therefore it is natural."