vested interest (in something)a personal reason for wanting something to happen, especially because you get some advantage from itThey have a vested interest in keeping the club as exclusive as possible.Vested interests (= people with a vested interest) are opposing the plan.She thinks that lawyers have a vested interest in making the legal process move slowly.
See vested interest in the Oxford Learner's Dictionary of Academic EnglishSee vested interest in the Oxford Advanced American Dictionary
