Alienation of Affection

In United States law, alienation of affections is a tort action brought by a deserted spouse against a third party alleged to be responsible for the failure of the marriage. The defendant in an alienation of affections suit is typically an adulterous spouse's lover, although family members, counselors, or clergy members who have advised a spouse to seek divorce have also been sued for alienation of affections.
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Noun
1. a tort based on willful and malicious interference with the marriage relation by a third party without justification or excuse
(hypernym) tort, civil wrong