Aloysius \a-loy-sius\ as a boy's name is pronounced al-oo-ISH-us. It is of Old German origin, and the meaning of Aloysius is "famous warrior". Latin version of Luigi or Louis, also related to Clovis and Ludwig. The name was rather common in Italy in the Middle Ages, and was by made popular by the 16th-century Italian saint Aloysius, patron saint of students. Sixteen kings of France bore the French form of this name, Louis.