'Great King' in the Bible

My mind reels, horror overwhelms me;The twilight I longed for has been turned into fear and trembling for me.

Then the Rabshakeh said to them, “Say to Hezekiah, ‘This is what the great king, the king of Assyria says, “What is [the reason for] this confidence that you have?

Then the Rabshakeh stood and called out with a loud voice in Judean (Hebrew): “Hear the words of the great king, the king of Assyria.