A polity is an organized group of people living under a shared system of government. Countries, cities, and states are all polities. Ancient Athens was a polity, and so is the United States today. Any community that has organized itself with rules, leaders, and a way of making decisions counts as a polity.

The word is more formal than “country” or “nation,” and that's actually what makes it useful. Polity covers all kinds of political organization, not just modern nations. A medieval kingdom was a polity. A Native American confederacy was a polity. A small city-state like ancient Sparta was a polity. The word lets you talk about very different societies without having to pick a more specific label that might not quite fit.

You'll encounter polity most often in history and social studies, where it helps describe how people have governed themselves across time and place.