I was hoping my brother would be able to contribute, but he wasn't able to come over for spring break. Oh well. Welcome to "Doggerel," a series I'll be running dealing with words that are overused, misused, or just plain meaningless. Tonight, I'll be talking about the word "supernatural." I've only come across one coherent definition of "supernatural." Don't hold your breath, but here it is:
Supernatural abilities are magical and go away in an antimagic field but are not subject to spell resistance. Supernatural abilities cannot be dispelled. Using a supernatural ability is a standard action unless noted otherwise. Supernatural abilities may have a use limit or be useable at will, just like spell-like abilities. However, supernatural abilities do not provoke attacks of opportunity and never require Concentration checks. Unless otherwise noted, a supernatural ability has an effective caster level equal to the creature's Hit Dice.That's from the D&D Monster Manual 3.5. Not terribly impressive, is it? Doesn't really apply to the real world, though it is handy for the game, especially since the Rockstar team up there can teleport without provoking attacks of opportunity.
The saving throw (if any) against a supernatural ability is 10 + 1/2 the creature's HD + the creature's ability modifier (usually Charisma).
The problem with real world definitions is that methodical naturalism doesn't really leave room for the supernatural: Anything that has an observable effect falls under methodical naturalism and is subject to the scientific method. The only way something could be supernatural is if it has no observable effects. "Unobservable effects" strikes me as a contradiction, since I would think such effects would either build up to an observable level, or useless, since they might as well be in another, completely separate universe. If something doesn't have effects observable or otherwise, it might as well not exist at all.
The common use definition might have its uses for determining if something is eligible for the Randi Challenge, but if anything passes through that, it'll be considered natural afterwards (and no, Randi can't use that to get out of paying: If you do what you claim to do, he's already under a legally binding contract to pay).