Hidden, out of sight or inconspicuous.
Dark, faint or indistinct.
Difficult to understand.
Not well-known.
Unknown or uncertain; unclear.
To hide, put out of sight etc.
To render obscure; to darken; to make dim; to keep in the dark; to hide; to make less visible, intelligible, legible, glorious, beautiful, or illustrious.
Occult, mysterious.
Having oracle-like predicting powers, clairvoyant.
Of or pertaining to or resembling a sibyl or female oracle, especially the Cumaean Sibyl and the Sibylline Books.
Excessively and exorbitantly expensive. (In allusion to the Sibyl who sold three books to Tarquinius Superbus at the price of the original nine.)
One of the Sibylline Oracles or Sibylline Books.