A levy is an official demand, usually by a government, to collect money from people. When a town levies a tax to build a new library, it means the government is requiring residents to pay a certain amount to fund the project. The word can be a noun (the levy itself) or a verb (to levy something).

Governments levy taxes to pay for schools, roads, police departments, and other public services. A school district might levy a special tax to upgrade its buildings. A state might levy fees on vehicle registrations. The key idea is that a levy isn't optional: it's an official requirement backed by law.

Historically, kings and rulers would levy taxes on their subjects, sometimes demanding grain, livestock, or labor instead of money. Medieval lords might levy troops, requiring each village to provide soldiers for the army. Today, when people say their property taxes were levied, they mean the government calculated what they owe and officially demanded payment.

A similar-sounding word with a different spelling is levee. A levee is an embankment built along a river to prevent flooding. The levees protecting New Orleans are massive earth walls designed to hold back water during storms.