A "fanatic" is a person who has an extreme and uncritical enthusiasm for a particular cause, activity, or belief. This intense passion often leads them to disregard opposing viewpoints and can result in obsessive behavior. Fanatics can be found in various areas, including sports, religion, and politics, where their fervor may influence their actions and decisions. While enthusiasm can be positive, fanaticism can lead to negative consequences, such as intolerance or aggression towards others. It is important to recognize the difference between healthy passion and fanaticism, as the latter can create divisions and conflict within communities and among individuals who hold differing beliefs or interests, such as sports fans or political activists.