Ghayba

Ghayba or al-Ghayba (الغيبة, 'Occultation', 'Concealment') may refer to:


 * Occultation (Islam), Shi'ite eschatological belief in the concealment and subsequent reemergence of an Imam or Mahdi, who will establish justice and peace on earth in the end of time
 * Minor Occultation, first period of concealment of the Imam (874–941) in Twelver Shi'ism, during which the twelfth and last Imam Muhammad al-Mahdi (c. 868–874) is believed to have communicated regularly with his followers through four successive agents
 * Major Occultation, second period of concealment of the Imam (941–present) in Twelver Shi'ism, during which the hidden Imam Muhammad al-Mahdi is believed to be without agent


 * (al-Nu'mani), sometimes simply known as, a work on the occultation of Muhammad al-Mahdi by the Twelver Shi'ite scholar Muhammad ibn Ibrahim al-Nu'mani (died c. 970)
 * (al-Tusi), sometimes simply known as, a work on the occultation of Muhammad al-Mahdi by the Twelver Shi'ite scholar Shaykh Tusi (995–1067)