Arabic Isre’il اسراىيلThe surname of Ya’qub (Jacob). Al-Baizawi says the meaning of Isr’il in Hebrew is Sufwatu ‘llah i.e. “the sincere friend of God”; or, as some say, Abdu’llah, “the servant of God. Banu Isra’il, “the children of Israel,” is a term the frequently occurs in the Qur’an. The XVIIth chapter of the Qur’an, known as the Suratu ‘l-Mi’raj, is also called the Suratu Bani Isra’il.
Based on Hughes, Dictionary of Islam