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Webster 1828 Edition
Incest
IN'CEST
,Noun.
The crime of cohabitation or sexual commerce between persons related within the degrees wherein marriage is prohibited by the law of a country.
Spiritual incest, is a like crime committed between persons who have a spiritual alliance by means of baptism or confirmation. It is also understood of a vicar or other beneficiary, who holds two benefices, the one depending on the collation of the other.