Since aristos means "best" in Greek, ancient Greeks such as Plato and Aristotle used the word aristocracy to mean a system of rule by the best people—that is, those who deserved to rule because of their intelligence and moral excellence. But this kind of "best" soon became something you could inherit from your parents. The United States has no formal aristocracy—no noble titles such as baron or marquis that stay in the family—but certain American families have achieved an almost aristocratic status because of the wealth they've held onto for generations.