Prophetiae Sibyllarum ("Sibylline Prophecies" or "Sibylline Oracles") are a series of twelve motets by the Franco-Flemish composer Orlande de Lassus. The works are known for their extremely chromaticism. The Delphic Sibyl may have been related to the well-known Oracle at Delphi. The sibyl was the sister (or daughter) of Apollo.
