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adultery vs. fornication

adultery

[uh-duhl-tuh-ree] / əˈdʌl tə ri /

noun

adulteries

voluntary sexual intercourse between a married person and someone other than their lawful spouse.

fornication

[fawr-ni-key-shuhn] / ˌfɔr nɪˈkeɪ ʃən /

voluntary sexual intercourse between two unmarried persons or two persons not married to each other.
Bible. idolatry.