Watson's Biblical & Theological Dictionary 
is an organized and living body, endowed with sensation. Minerals are said to grow or increase, plants to grow and live, and animals alone to have sensation. The Hebrews distinguished animals into pure and impure, clean and unclean; or those which might be eaten and offered, and those whose use was prohibited. The sacrifices which they offered, were,
1. Of the beeve kind; a cow, bull, or calf. The ox could not be offered, because it was mutilated; and when it is said oxen were sacrificed, we are to understand bulls, Leviticus 22:18-19 . Calmet thinks, that the mutilation of animals was neither permitted, nor used, among the Israelites.
2. Of the goat kind; a he-goat, a she-goat, or kid, Leviticus 22:24 .
3. Of the sheep kind; a ewe, ram, or lamb. When it is said sheep are offered, rams are chiefly meant, especially in burnt-offerings and sacrifices for sin; for as to peace-offerings, or sacrifices of pure devotion, a female might be sometimes offered, provided it was pure, and without blemish, Leviticus 3:1 .
Besides these three sorts of animals, used in sacrifices, many others might be eaten, wild or tame; as the stag, the roe-buck, and in general all that have cloven feet, or that chew the cud, Leviticus 9:2-3 , &c. All that have not cloven hoofs, and do not chew the cud, were esteemed impure, and could neither be offered nor eaten. The fat of all sorts of animals sacrificed was forbidden to be eaten. The blood of all kinds of animals generally, and in all cases, was prohibited on pain of death, Leviticus 3:17; Leviticus 7:23-27 . Neither did the Israelites eat animals which had been taken and touched by a devouring or impure beast, as a dog, a wolf, a boar, &c, Exodus 22:3; nor of any animal that died of itself. Whoever touched its carcass was impure until the evening; and till that time, and before he had washed his clothes, he did not return to the company of other Jews, Leviticus 11:39-40; Leviticus 17:15; Leviticus 22:8 . Fish that had neither fins nor scales were unclean, Leviticus 11:20 . Birds which walk on the ground with four feet, as bats, and flies that have many feet, were impure. The law, however, excepts locusts, which have their hind feet higher than those before, and rather leap than walk. Those were clean, and might be eaten, Leviticus 11:21-22 , as they still are in Palestine. The distinction between clean and unclean animals has been variously accounted for. Some have thought it symbolical, intended to teach the avoidance of those evil qualities for which the unclean animals were remarkable; others, that, in order that the Hebrews might be preserved from idolatry, they were commanded to kill and eat many animals which were sacred among the Egyptians, and were taught to look with abhorrence upon others which they reverenced. Others have found a reason in the unwholesomeness of the flesh of the creatures pronounced by the law to be unclean, so that they resolve the whole into a sanative regulation. But it is not to be forgotten that this division of animals into clean and unclean existed both before the law of Moses, and even prior to the flood. The foundation of it was therefore clearly sacrificial; for before the deluge it could not have reference to health, since animal food was not allowed to men prior to the deluge; and as no other ground for the distinction appears, except that of sacrifice, it must therefore have had reference to the selection of victims to be solemnly offered to God, as a part of worship, and as the means of drawing near to him by expiatory rites for the forgiveness of sins. Some, it is true, have regarded this distinction of clean and unclean beasts as used by Moses by way of prolepsis, or anticipation,—a notion which, if it could not be refuted by the context, would be perfectly arbitrary. Not only are the beasts, which Noah was to receive, spoken of as clean and unclean; but it will be noticed, that, in the command to take them into the ark, a difference is made in the number to be preserved—the clean being to be received by sevens, and the unclean by two of a kind. This shows that this distinction among beasts had been established in the time of Noah; and thus the assumption of a prolepsis is refuted. The critical attempts which have been made to show that animals were allowed to man for food, previous to the flood, have wholly failed.
A second argument is furnished by the prohibition of blood for food, after animals had been granted to man for his sustenance along with the "herb of the field." This prohibition is repeated by Moses to the Israelites, with this explanation:—"I have given it upon the altar to make an atonement for your souls." From this it has indeed been argued, that the doctrine of the atoning power of blood was new, and was then, for the first time, announced by Moses, or the same reason for the prohibition would have been given to Noah. To this we may reply,
1. That unless the same be supposed as the ground of the prohibition of blood to Noah, as that given by Moses to the Jews, no reason at all can be conceived for this restraint being put upon the appetite of mankind from Noah to Moses.
2. That it is a mistake to suppose, that the declaration of Moses to the Jews, that God had "given them the blood for an atonement," is an additional reason for the interdict, not to be found in the original prohibition to Noah. The whole passage in Leviticus 17, is, "And thou shalt say to them, Whatsoever man there be of the house of Israel, or of the strangers that sojourn among you, that eateth any manner of blood, I will even set my face against that soul that eateth blood, and I will cut him off from among his people: FOR THE LIFE of the flesh is in the blood; and I
have given it upon the altar, to make atonement for your souls: for it is the BLOOD (or LIFE) that maketh atonement for the soul." The great reason, then, of the prohibition of blood is, that it is the LIFE; and what follows respecting atonement is exegetical of this reason; the life is in the blood, and the blood or life is given as an atonement. Now, by turning to the original prohibition of Genesis, we find that precisely the same reason is given: "But the flesh with the blood, which is the life thereof, shall ye not eat." The reason, then, being the same, the question is, whether the exegesis added by Moses must not necessarily be understood in the general reason given for the restraint to Noah. Blood is prohibited for this cause, that it is the life; and Moses adds, that it is "the blood," or life, "which makes atonement." Let any one attempt to discover any cause for the prohibition of blood to Noah, in the mere circumstance that it is "the life," and he will find it impossible. It is no reason at all, moral or instituted, except that as it was life substituted for life, the life of the animal in sacrifice for the life of man, and that it had a sacred appropriation. The manner, too, in which Moses introduces the subject is indicative that, although he was renewing a prohibition, he was not publishing a "new doctrine;" he does not teach his people that God had then given, or appointed, blood to make atonement; but he prohibits them from eating it, because he had made this appointment, without reference to time, and as a subject with which they were familiar. Because the blood was the life, it was sprinkled upon, and poured out at, the altar: and we have in the sacrifice of the paschal lamb, and the sprinkling of its blood, a sufficient proof, that, before the giving of the law, not only was blood not eaten, but was appropriated to a sacred sacrificial purpose. Nor was this confined to the Jews; it was customary with the Romans and Greeks, who, in like manner, poured out and sprinkled the blood of victims at their altars, a rite derived, probably, from the Egyptians, as they derived it, not from Moses, but from the sons of Noah. The notion, indeed, that the blood of the victims was peculiarly sacred to the gods, is impressed upon all ancient Pagan mythology.
If, therefore, the distinction of animals into clean and unclean existed before the flood, and was founded upon the practice of animal sacrifice, we have not only a proof of the antiquity of that practice, but that it was of divine institution and appointment, since almighty God gave laws for its right and acceptable performance. Still farther, if animal sacrifice was of divine appointment, it must be concluded to be typical only, and designed to teach the great doctrine of moral atonement, and to direct faith to the only true sacrifice which could take away the sins of men;—"the Lamb slain from the foundation of the world,"—the victim "without spot," who suffered the just for the unjust, that he might bring us to God. See Sacrifices .
Webster's Dictionary 
(1): (a.) Consisting of the flesh of animals; as, animal food.
(2): (n.) An organized living being endowed with sensation and the power of voluntary motion, and also characterized by taking its food into an internal cavity or stomach for digestion; by giving carbonic acid to the air and taking oxygen in the process of respiration; and by increasing in motive power or active aggressive force with progress to maturity.
(3): (n.) One of the lower animals; a brute or beast, as distinguished from man; as, men and animals.
(4): (a.) Of or relating to animals; as, animal functions.
(5): (a.) Pertaining to the merely sentient part of a creature, as distinguished from the intellectual, rational, or spiritual part; as, the animal passions or appetites.
King James Dictionary 
AN'IMAL, n. L. animal, from anima, air, breath, soul.
An organized body, endowed with life and the power of voluntary motion a living, sensitive, locomotive body as, man is an intelligent animal. Animals are essentially distinguished from plants by the property of sensation. The contractile property of some plants, as the mimosa, has the appearance of the effect of sensation, but it may be merely the effect of irritability.
The distinction here made between animals and vegetables, may not be philosophically accurate for we cannot perhaps ascertain the precise limit between the two kinds of beings, but this is sufficiently correct for common practical purposes.
The history of animals is called zoology.
By way of contempt, a dull person is called a stupid animal.
Easton's Bible Dictionary 
Genesis 7:2 Deuteronomy 14:3-20 Leviticus 11