What is "vathek"

Vathek (alternatively titled Vathek, an Arabian Tale or The History of the Caliph Vathek) is a Gothic novel written by William Beckford. It was composed in French beginning in 1782, and then translated into English by Reverend Samuel Henley in which form it was first published in 1786 without Beckford's name as An Arabian Tale, From an Unpublished Manuscript, claiming to be translated directly from Arabic. The first French edition, titled simply as Vathek, was published in December 1786 (postdated 1787). In the twentieth century some editions include The Episodes of Vathek (Vathek et ses épisodes), three related tales intended by Beckford to be so incorporated, but omitted from the original edition and published separately long after his death.