sílā

… was often confused with the siʿlā, also female; the siʿlā, however, was a witchlike species of jinn, immutable in shape. A ghūl stalked the desert, often in the guise of an attractive woman, trying to distract travelers, and, when successful, killed and ate them. The sole defense that one had…

…ʿifrīt (diabolical, evil spirits), and siʿlā (treacherous spirits of invariable form) constitute classes of jinn.