Cherub; Cherubim

Boyd’s Bible Dictionary:

(terrible). Guards of Paradise (Gen. 3:24); and the mercy seat (Ex. 25:18). Wrought in gold or wood (Ex. 36:35; 37:7-9). Of immense size in Solomon’s Temple (1 Kings 6:27). Four-winged and four-faced (Ezek. 1:6; 10:14; Rev. 4:8).

Concise Bible Dictionary:

Representatives of God’s power in creation and judicial government. They were placed at Eden to keep the tree of life after the fall of man (Gen. 3:24). They were depicted in needlework and in carving both in the tabernacle and the temple, and two of them with wings were represented as overshadowing the mercy-seat (Ex. 25:18-22; Ex. 26:1, 31; Ex. 37:7-9; 1 Kings 6:23-35; 1 Kings 8:6-7). In the visions of Ezekiel cherubim were seen in connection with the wheels, representing the glory and course of God’s government in active judgment of Israel. They are called “living creatures” in Ezekiel 1, with the faces of a man (intelligence), of a lion (strength), of an ox (plodding endurance), and of an eagle (swiftness): see also Ezekiel 10 where they are called “cherubims,” and compare Revelation 4:6-9, where in the AV the four living creatures are unhappily called “beasts.”
The winged bulls which were placed at the entrances of the Assyrian palaces were probably traditions of the cherubim. In the Accadian language they were termed kirubu, and were thought to preserve the places from the entrance of evil spirits.

Jackson’s Dictionary of Scripture Proper Names:

as if contending, Cherubim = masculine plural of Cherub