Sadr was primarily used in the Iranian world to designate an exceptional person, such as a scholar.
It was initially used as a personal title for major religious scholars in Transoxiana, then also for high-ranking administrative figures, and from c. 1380 until the late 18th-century, for the head of the religious authority of a nation.
It was then ultimately used for high-ranking figures in Qajar Iran, including the grand vizier.
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