a personal reason for wanting sth to happen, especially because you get some financial advantage from it （个人的）既得利益◆The bank has a vested interest in seeing your business succeed. 银行希望看到你事业成功。
a group of people who have a personal reason of this kind for wanting sth to happen 特权阶层◆The government will challenge the vested interests that control so much power. 政府将向控制大权的特权阶层发起挑战。