Satan (שטן) is "the Evil One," often called Lucifer, the Devil, or Beelzebub (בעל זבוב). He is an antagonist to God and his church.

From the Hebrew "Ha-Satan" (השטן), literally the "Accuser." Also know as the "Devil" or the "Evil One", Satan is at the head of the spiritual forces arrayed against God, His elect, and the holy angels.