Lewis & Short

Beelzĕbŭb, indecl., or Beelzĕbŭl, ūlis, m., = Βεελζεβούβ or Βεελζεβούλ, Heb. [??] or [??]; in eccl. Lat. Beelzebub, the chief of evil spirits, Vulg. Luc. 11, 15; Tert. adv. Marc. 4, 26; Prud. στεφ. 2, 267.