The host of heaven; the stars, which the Gentiles had transformed into gods. See Poole on "Deuteronomy 4:19".
Related Commentaries of 2 Kings 21:3
2 Kings 21:3
3 For he built up again the high places which Hezekiah his father had destroyed; and he reared up altars for Baal, and made a grove, as did Ahab king of Israel; and worshipped all the host of heaven, and served them.