Boyd’s Bible Dictionary:
God’s knowledge of the future
(Acts 2:23; 15:18; 1 Peter 1:2).
Concise Bible Dictionary:
A knowledge of persons and events before they exist. It is one of the divine attributes of God, by which persons were foreknown of Him and events determined. It is a capacity altogether beyond the mind of man to grasp (Acts 2:23; Rom. 8:29; Rom. 11:2; 1 Pet. 1:2). The verb is also translated “know before” (2 Pet. 3:17); and “foreordain” (1 Pet. 1:20).
From Anstey’s Doctrinal Definitions:
This is an attribute of deity which refers to God’s ability to know all things before they happen (Isa. 41:2-4; Acts 2:23; 15:18; Rom. 8:29; 11:2; 1 Peter 1:2). It is different from divine providence, which is God’s power to guide and direct all things on earth according to His will (Eph. 1:11; Prov. 21:1). With foreknowledge and providence, God is well able to predict the future, for He controls world history.