pious: [17] Pious is one of a nexus of English words descended from Latin pius, an adjective of unknown origin. Its derivative pietās has given English piety and pity, and the derived verb piāre ‘appease, atone’ lies behind English expiate [16]. Pious itself was probably borrowed direct from Latin. => expiate, piety, pity[pious etymology, pious origin, 英语词源]