ETYM Latin sibylla, Greek.
1. A woman who tells fortunes.
2. (Ancient Greece and Rome) A woman who was regarded as an oracle or prophet.
In Roman mythology, one of many prophetic priestesses, notably one from Cumae near Naples. She offered to sell to the legendary king of Rome, Tarquinius Superbus, nine collections of prophecies, the Sibylline Books, but the price was too high. When she had destroyed all but three, he bought those for the identical price, and they were kept for consultation in emergency at Rome.