Masawaih al-Mardini (Yahy? ibn Masawaih al-Mardini; known as Mesue the Younger) was a Syrian physician. He was born in Mardin, Upper Mesopotamia. After working in Baghdad, he entered to the service of the Fatimid caliph Al-Hakim bi-Amr Allah. He died in 1015 in Cairo at the age of ninety