I would define supernatural as anything that contradicts the laws of nature. The first problem being the underlying assumption that we know all of the rules of nature. The second being that if phenomenon follows any pattern at all, then it would appear to be following a natural law of some kind. Which leaves me with a more personal definition: supernatural is that which one person doesn't understand and intends never to understand. Obviously, it's in the eye of the beholder.
If there is a god, I want to believe that there is a god. If there is not a god, I want to believe that there is no god.
