Hastings' Dictionary of the New Testament 
Supernatural —It is generally recognized that this word is difficult to define, and its definitions are difficult to defend. The reason of this is simple. It is not a scientific but a popular term, and is therefore liable to the ambiguity and vagueness besetting words which really involve metaphysical considerations, but which have grown into use without any proper discussion of the metaphysical questions involved. The word means that which is beyond or above nature ; but the word ‘nature’ is ambiguous, and it is therefore uncertain what, if anything, corresponds to the word ‘supernatural.’ In ordinary speech, ‘supernatural’ would appear to mean anything outside the ordinary course of the phenomenal world. Everything connected with ghosts, for instance, is described as supernatural, and such things as telepathy are said to border on the supernatural. But even in such cases as this the idea attached to the word is not clear. A ghost, let us say, raps on a table, or makes the sound of a carriage driving up to the door. These are perfectly natural and ordinary sounds: they are called ‘supernatural’ only in the sense that they are produced in an extraordinary way. And by this is apparently meant that the spiritual or volitional cause of the sounds is in an unusual relation to the material world. A chairman rapping on the table at a meeting, or a cabman driving up to the door, is a spiritual or volitional cause of the sounds produced, but he is in the ordinary relation to matter. So the phenomena of telepathy are said to border on the supernatural, because in them effects are produced in a way which the popular mind regards as peculiarly mysterious.
Those who hold that the world was made and is ruled by God, have to imagine to themselves in some shape the mode in which God exercises His sway. For ordinary purposes it suffices to treat the world as an independent organization, carried on by laws which are regarded as invariable, and it is unnecessary to refer continually to the Primary Cause of all. This view of the world is harmless enough, but it has the disadvantage of developing an inveterate tendency or habit of thought, by which the world is set up over against God, as equivalent to ‘nature’ or the ‘natural order’; while all action on the part of God is treated as having the character of disturbance or interference in an order which possesses independent rights, or as being supernatural, in virtue of the fact that it does interfere or disturb. From this habit of mind come all those phrases by which miracles are described as ‘suspensions of the order of nature,’ and the like. If a person under the influence of this habit of thought meets with the suggestion that miracles are themselves orderly, and illustrate a higher law than that of ordinary experience, he is disquieted, because he thinks that in losing the character of disturbance, miracles lose their ‘supernatural’ character.
Two things are clear in regard to this difficulty: (1) that the source of it lies in the (unverified) dualism between God and the world; (2) that there is a real point involved in the distress of the plain man at what he thinks is an attenuation of the meaning of miracle. We will consider the second point first. It is manifest that if the law which governs miracle differed from that governing ordinary experience, merely in complexity, the distinction of natural and supernatural would disappear; so far the plain man is right. A conjurer does not profess to use any but the most ordinary laws: yet a savage might look upon the common trick of bringing live pigeons out of a hat as a real, creative ‘supernatural’ act. Some of the language used by critics of miracles and the term ‘supernatural’ have a tendency to bring these events down to the level of tricks or deceptions. It is said, for instance, that a fuller knowledge of natural processes would lead us to see in the miracle at the wedding-feast at Cana merely an acceleration of such processes, which would quite surrender itself to ordinary methods of interpretation. If this were true, the miracle would cease to be in any sense ‘supernatural’; it would be merely a special, imperfectly analyzed case of an ordinary occurrence. This is a real attenuation of the meaning of the word, and the plain man is right in objecting to it. But he is wrong if he objects to it on the ground, expressed or implied, that Divine action is necessarily explosive or disruptive; for this would mean that Divine action is irrational, and that a miracle must be as great a marvel to God as to man. Whatever the appearance of the supernatural to us, to God it must appear rational and orderly. God is the author of nature and its laws. Their uniformity represents His normal action and will for the world. But nature and its laws have no independent validity or rights as against God. They are entirely at His disposal and under His control. If, for whatever reason, He diverges from what is normal, it will be for sufficient cause. He will act in a new way upon the old material, reminding man of the dependence of all upon Him. And the difference between the normal and the abnormal action does not consist in the nature of the laws employed, as if the usual operation of natural law were broken or suspended by some intrusive and alien force; but in the fact that the action of God upon the order of created being is in one case what we expect, in the other widely different. There is no reason why the word ‘supernatural,’ which will certainly not be driven out of our vocabulary, should not be used as a label for certain characteristic groups of actions and events. It appears necessary to vindicate the freedom of God to take such action: otherwise we subject Him to the tyranny of His own laws. But there is no reason to associate the word with a variety of half-conscious dualistic assumptions, which cannot be defended in theory. See also art. Miracles.
Thomas B. Strong.
Webster's Dictionary 
(a.) Being beyond, or exceeding, the power or laws of nature; miraculous.
Cyclopedia of Biblical, Theological and Ecclesiastical Literature 
This is a word which is popularly used in opposition to "natural," things and events which are not within the ordinary concrete experience and knowledge of mankind being looked upon as forming part of a separate system of things and events. "That is supernatural, whatever it be, that is either not in the chain of natural cause and effect, or which acts on the chain of cause and effect in nature from without "the chain" (Bushnell, Nature and the Supernatural). M'Cosh (On the Supernatural, p. 146, 147) gives this definition: "We may speak of whatever is supposed to be beyond the natural asprete-natural. The phrase will apply not only to the divine action, but to the agency of such beings as ghosts and demons — to b all such operations as witchcraft and necromancy. We may reserve the phrase supernatural to the Supreme Being and to the works performed by him, and to the objects created by him beyond the natural a sphere, such as angels and the world to cone. We would confine the word miracle to those events which were wrought in our world as a sign or proof of God making a supernatural interposition or a revelation to man. We must not look upon creation as supernatural, but we do look upon it as miraculous." So far as our investigation pushes out into the world of nature, we find that law and order exist, and every increase of knowledge reveals to us further illustrations of the assertion that "order is Heaven's first law." Belief in the supernatural does not, therefore, require us to believe in any violation of law, since all reasoning which starts from what we know leads to the conclusion that "supernatural phenomena are as much the result of law as phenomena which are called ‘ natural.'" (See Miracle).