Definition of "sibyl"

A Sybill that had numbred in the worldThe Sun to courſe, two hundred compaſſes,In her Prophetticke furie ſow'd the Worke:

c. 1603–1604 (date written), William Shakespeare, “The Tragedie of Othello, the Moore of Venice”, in Mr. William Shakespeares Comedies, Histories, & Tragedies […] (First Folio), London: […] Isaac Iaggard, and Ed[ward] Blount, published 1623, [Act III, scene iv], page 327

"Are you very anxious," asked he, "to consult the sibyl?" "Nay," replied Francesea; "I want faith." "You will," replied he, "nevertheless be amused with Madame de I'Hôpital's tact; she knows enough of the history of the individuals around to give a shrewd guess at the favourite fantasy of each, and that it will be successful is the summing up of her prophecy. She tells each what he wishes, and so obtains an easy belief."

1834, L[etitia] E[lizabeth] L[andon], chapter V, in Francesca Carrara. […], volume II, London: Richard Bentley, […], (successor to Henry Colburn), page 45

`Nay, wait, Kallikrates,' said Ayesha, who, standing with the lamp raised above her head, flooding with its light her own rich beauty and the cold wonder of the death-clothed form upon the bier, resembled an inspired Sibyl rather than a woman, as she rolled out her majestic sentences with a grandeur and a freedom of utterance which I am, alas! quite unable to reproduce.

1886 October – 1887 January, H[enry] Rider Haggard, She: A History of Adventure, London: Longmans, Green, and Co., published 1887

I used to read these tales in Homer when I was a lad. Then the Sibyl! I saw her at Cumae with my own eyes hanging in a jar; and when the boys cried to her, ‘Sibyl, what would you?' she'd answer, ‘I would die,'-- both of ‘em speaking Greek."

1922 T. S. Eliot, The Wasteland: Epigraph (translated from 61 Petronius' The Satyricon: Chapter 8, Lines 80 -86)