Abdāl (Arabic: أبدال‎) lit: substitutes, but which can also mean "generous" [karīm] and "noble" [sharīf]) is a term used in Islamic metaphysics and Islamic mysticism, both Sunni and Shiite, to refer to a particularly important group of God's saints. In the tradition of Sunni Islam in particular, the concept attained an especially important position in the writings of the Sunni mystics and theologians, whence it appears in the works of Sunni authorities as diverse as Abu Talib al-Makki (d. 956), Ali Hujwiri (d. 1072), Ibn Asakir (d. 1076), Khwaja Abdullah Ansari (d. 1088), and Ibn Khaldun (d. 1406).