impious has definitions from the field of religion
1
[ adjective ] (religion) lacking piety or reverence for a god

Used in print

(Chicago Daily Tribune...)

Directed by Grigory_Kozintsev in a tempo that is studiously slow , he develops a sense of a high tradition shining brightly and passing gravely through an impious world .

(S. J. Perelman, The Rising Gorge. New York:...)

Well , ordinarily he is , except ( as the Wheel_of_the_Law specifies ) toward impious folk who steal , disturb , or maltreat the Presence .

2
[ adjective ] lacking due respect or dutifulness

Synonyms

undutiful

Examples

"impious toward one's parents" "an undutiful son"

Related terms

disrespectful

3
[ adjective ] (religion) lacking piety and reverence for a god

Synonyms

ungodly

Related terms

irreligious

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