unbelieving has definitions from the field of religion
1
[ adjective ] holding that only material phenomena can be known and knowledge of spiritual matters or ultimate causes is impossible

Synonyms

nescient

Related terms

agnostic

2
[ adjective ] (religion) rejecting any belief in gods

Related terms

irreligious

3
[ adjective ] (religion) denying or questioning the tenets of especially a religion

Examples

"a skeptical approach to the nature of miracles"

Related terms

incredulous

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