Definition of "Sybil"

Sybil

noun
plural Sybils
1. Prophetess; hag.
  Quotations
  The Library looked tranquil enough as I entered it, and the Sybil—if Sybil she were, was seated snugly enough in an easy chair at the chimney-corner.
  1847 October 16, Currer Bell [pseudonym; Charlotte Brontë], chapter IV, in Jane Eyre. An Autobiography. […], volume II, London: Smith, Elder, and Co., […], page 90
2. (computer security) Ellipsis of Sybil attack.
proper noun
1. A female given name from Ancient Greek, the most popular spelling variant of Sibyl since the 19th century.
  Quotations
  "I beg your pardon," said Egremont blushing; "I was reading your name. I thought I was reading it to myself. Sybil Gerard! What a beautiful name is Sybil!" "My mother's name," said Gerard; "and my grandame's name, and a name I believe that has been about our hearth as long as our race; and that's a very long time indeed," he added smiling, "for we were tall men in King John's reign, as I have heard say."
  1845, Benjamin Disraeli, Sybil, Book 3, Chapter 5