The title, “Great King,” employs the Hebrew word gadol, which refers to greatness in size and importance and relates to magnify which is also used of God, a call to increase His status (Ps. 40:16).
The Hebrew word melekh had a broad meaning, applying to several classes of leading “magisterial” figures; our modern “king” is just one possibility.
The sense of this name is that God is the supreme ruler over men and the universe. Similar names, like King of heaven, King of kings, King of Jacob or Israel, and Eternal King, together state the full extent of His rule over the nations for all time.
Great King in Hebrew:
Strong’s Concordance numbers: 4228, 1419
Bible references: Pss. 47:2; 95:3; Mal. 1:14
But cursed be the deceiver, which hath in his flock a male, and voweth, and sacrificeth unto the Lord a corrupt thing: for I am a great King, saith the Lord of hosts, and my name is dreadful among the heathen. (Malachi 1:14 KJV)