Supernatural

What does it mean to be supernatural? If something does or can interact with something or someone in this system, is it truly supernatural? If by making contact with a system can that phenomenon remain outside of, or 'super' of that system? Is God supernatural? Does He exist outside of this system? If He interacts with this system does He become part of this system? If He interacts with this system does His system become continous with this system? How about a one-way flow valve that allows influence into this system. Could it be a controlled interaction such that it flows one-way? He may interact in this system but this system is blocked from interacting back?