Adjective impious has 3 senses
- impious - lacking piety or reverence for a god
Antonyms: pious, devotional, godly, reverent, worshipful, holier-than-thou, pietistic, pietistical, pharisaic, pharisaical, sanctimonious, self-righteous, prayerful
- impious, undutiful - lacking due respect or dutifulness; "impious toward one's parents"; "an undutiful son"
Antonym: respectful (indirect, via disrespectful)
- impious, ungodly - lacking piety and reverence for a god
Antonym: religious (indirect, via irreligious)
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