Zīj as-Sindhind (Arabic: زيج السندهند الكبير, Zīj as‐Sindhind al‐kabīr, lit. "Great astronomical tables of the Sindhind"; from Sanskrit siddhānta, "system" or "treatise") is a work of zij (astronomical handbook with tables used to calculate celestial positions) brought in the early 770s AD to the court of Caliph al-Mansur in Baghdad from India. Al-Mansur requested an Arabic translation of this work from the Sanskrit. The 8th-century astronomer and translator Muḥammad ibn Ibrāhīm al-Fazārī is known to have contributed to this translation.[1] In his book Ṭabaqāt al-ʼUmam "Categories of Nations",[2] Said al-Andalusi informs that others who worked on it include ibn Sa'd and Muhammad ibn Musa al-Khwarizmi. He adds that its meaning is al-dahr al-dahir (infinite time or cyclic time).