The main stone forming the corner of the foundation of a building. Jesus Christ is called the chief cornerstone (Eph. 2: 20).

The stone that the builders refused has become the head stone of the corner, Ps. 118: 22 (Matt. 21: 42-44; Mark 12: 10; Luke 20: 17; Acts 4: 10-12). The Jews rejected the cornerstone, Jacob 4: 15-17.