Sultan

Sultan is an Islamic title, with several historical meanings. Originally, it was an Arabic language abstract noun meaning "strength", "authority", or "rulership", derived from a word meaning "authority" or "power".

Later, it came to be used as the title of certain rulers who claimed almost full sovereignty in practical terms (i.e., the lack of dependence on any higher ruler), without claiming the overall caliphate, or to refer to a powerful governor of a province within the caliphate.