Aristocracy refers to a small, privileged class of people who hold power and high social rank, usually because of the families they were born into rather than anything they achieved themselves. In many historical societies, aristocrats owned vast amounts of land, had special legal rights, and made important decisions about how their countries were run.

In medieval Europe, aristocrats had titles like duke, count, or baron. They lived in castles or grand estates while most people worked as farmers or craftspeople. An aristocrat's children automatically became aristocrats too, inheriting their parents' titles, lands, and privileges.

The word can also describe any group that holds itself above others. You might hear someone say that a school has an aristocracy of popular students who act as if they're more important than everyone else. When used this way, it's usually a criticism suggesting that the group thinks too highly of itself.

Britain still has an aristocracy with dukes and earls, though they have far less power than they once did. The United States never had an official aristocracy in its system of government, since the Founders believed that people should succeed through their own efforts and talents rather than inheriting special privileges. Thomas Jefferson wrote extensively about why he thought aristocracies were unfair and why America should reward merit instead.