Beelzebub is the Greek version of the name Baal-zebub, a pagan deity worshipped in the ancient Philistine city of Ekron during Old Testament times. The name means “the lord of flies” (2 Kings 1:2), which is significant as golden fly images have been discovered during excavations at ancient Philistine sites.

(Gr. form Beel'zebul), the name given to Satan, and found only in the New Testament (Matthew 10:25 ; Matthew 12:24 Matthew 12:27 ; Mark 3:22). It is probably the same as Baalzebub (q.v.), the god of Ekron, meaning "the lord of flies," or, as others think, "the lord of dung," or "the dung-god."

Beelzebub is also identified in the New Testament as the Devil, "the prince of demons". Biblical scholar Thomas Kelly Cheyne suggested that it might be a derogatory corruption of Ba'al-zəbûl, "Lord of the High Place" (i.e., Heaven) or "High Lord".