1.A special personal interest, usually financial, in an existing system, law, or institution, which hinders a person from making objective decisions regarding that system, law, or institution. A vested interest may be one which benefits a relative, or, in an extended sense, one which defends a person's own reputation or previously expressed views.
2.A right given to an employee by a pension plan, which cannot be taken away.
3.pl. The persons, corporations, or other groups which benefit most (usually financially) from the existing system of institutions, laws, and customs.
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