Athéisme.
ETYM Latin impietas, from impius impious; cf. French impiété. Related to Impious, Piety.
Unrighteousness by virtue of lacking respect for a god; SYN. impiousness.
ETYM Latin irreligio: cf. French irréligion. Related to In- not, and Religion.
The state of being irreligious; lack of religion; impiety.