Overview
Carnal knowledge is an archaic or legal euphemism for sexual intercourse. In modern statutes, the term "sexual penetration" is widely used, though with various definitions.
Biblical source
The term derives from carnal, meaning "of the flesh", and the Biblical usage of the verb know/knew, a euphemism for sexual conduct.
One examples of this usage is in the first part of the Bible, the Book of Genesis, which describes how Adam and Eve conceived their first child:
Also in Genesis is Lot's plea to the people of Sodom to whom he offered his virgin daughters, in place of his guests:
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