Pius is a male name, from the Latin word pius, the meaning of which is similar to the English "pious" from piety, meaning a desire and willingness to perform religious duties.The name is most commonly associated with Popes, twelve of whom (including three in the twentieth century and seven in the last 250 years), have taken the name Pius. Notable persons named Pius: Emperors Antoninus Pius - Roman Emperor 138 to 161 Popes » Main article Pope Pius Pope Pius I, saint, Pope 140/142 to 155 Pope Pius… (More on Pius)