adjective

1. having or showing religious devotion; zealous in the performance of religious obligations
2. springing from actual or pretended religious devotion or moral motives
3. seemingly virtuous; affecting virtue hypocritically
4. sacred, as distinguished from secular or profane
5. Archaic having or showing a sense of duty and loyalty to family, friends, etc.

Etymology: L pius, pious, devout, affectionate, good, prob. < IE *pwīyos < base *peu-, to clean > L purus, pure