Beelzebub (‘Lord of the Flies’) is an old deity worshipped by the Philistines in Ekron, considered a demon and one of the princes of Hell by Christians. He is also identified with Satan in the New Testament.
From 2 Kings 1:
And Ahaziah fell down through a lattice in his upper chamber that was in Samaria, and was sick: and he sent messengers, and said unto them, Go, enquire of Baalzebub the god of Ekron whether I shall recover of this disease.
(Ahaziah is then condemned to die by God’s words because he sought advice from Beelzebub instead of God.)