Come on Fester, you know exactly what's meant by the word.
I won't speak for Fester, but the meaning of nature is not a self-evident fact. Its meaning varies in scope according to preference.
The poster above just equated science with nature.
Yes, I know what the word "natural" means, but it is dependent solely upon each observer to apply it, and therefore it lacks both the openness and the precision science might enjoy as it is rightly defined. The word "natural" is loaded. Does it only apply to that which can be apprehended by human reason and senses? Then why do we bother to look into quantum theory?
Why study the force of gravity since we can only observe its effects and not its cause? Does natural only apply to processes that have been going on since the beginning of time? We don't even know when time began, let alone whether we've apprehended all dimensions of reality. Is there something "supernatural" about intelligence, design, or some combination of the two? No.
To insist that the word "natural" be attached to the definition of science is to throw an albatross around its neck, if only because "natural" is in the eyes of the beholder.