fornication

Fornication is generally consensual sexual intercourse between two people not married to each other. When one of the partners to consensual sexual intercourse is a married person, it may be described as adultery.
For many people, the term carries an overtone of moral or religious disapproval, but the significance of sexual acts to which the term is applied varies between religions, societies and cultures. In modern usage, the term is often replaced with a more judgment-neutral term like extramarital sex.

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