Slang (American English) for a wealthy person, and particularly that is targeted by fundraising campaigns (mainly political) for big contributions. A fat cat may also denote an important, influential, or famous person at a local, national or international level.

In a different context, it may also describe any wealthy person, especially an individual who has become very rich quickly or in a very short period of time through questionable means.

Yet in another context, it may refer to a person who has become idle, lazy or self-satisfied as the result of accumulated resources, an advantage or a privilege.

In British English, fact cat describes a businessman or politician who is disapproved by others or the community for the way he/ she uses their wealth and influence.