adj.1. a. Earnestly compliant in the observance of religion; reverent or devout: a pious nun.
b. Showing or characterized by religious devotion: pious observance.
c. Expressive of or used in religious devotion; devotional: pious readings.
2. a. Done for the benefit of others or with the intention of encouraging good: practicers of the noble lie and the pious fraud.
b. Sincere but wishful or far-fetched: a pious hope that the new method will work.
3. Self-righteous or sanctimonious: pious denunciations of sexual harassment.
4. Archaic Professing or exhibiting traditional morality; dutiful.