Wiktionary
al-amin
n. (context Islam English) a nickname of Muhammad, meaning ''the trusted one''
Wikipedia
Al-Amin
Muhammad ibn Harun al-Rashid, better known by his regnal name of al-Amin (April 787 – 24/25 September 813) , was the sixth Abbasid Caliph. He succeeded his father, Harun al-Rashid in 809 and ruled until he was deposed and killed in 813, during the civil war with his brother, al-Ma'mun.