Islamic Studies
Caliphate & Rulers: From the Rightly Guided Caliphs to the Ottoman Caliphate
Explanation
Dhun-Noorayn means 'possessor of two lights' because Uthman married two daughters of the Prophet ﷺ — Ruqayyah then Umm Kulthum.
Reference: Islamic Studies - Caliphate & Rulers
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