What word means the city where government meets?

The word that means the city where government meets, on the USCIS reading vocabulary list, is Capital. A capital is the seat of government for a country, state, or other political entity, and the word is distinct in spelling from capitol, which refers specifically to the building in which a legislature meets.

The capital of the United States is Washington, D.C., where D.C. stands for District of Columbia. Washington was selected as the permanent capital under the Residence Act of 1790, which gave President George Washington authority to choose a site along the Potomac River. The federal government moved from Philadelphia to Washington in 1800, and the city is governed under Article I, section 8, clause 17 of the Constitution as a federal district under the exclusive jurisdiction of Congress, separate from any state.

Each of the 50 states also has its own capital, where the state legislature, governor, and state supreme court conduct business. State capitals are not always the largest city in the state: New York's capital is Albany rather than New York City, California's capital is Sacramento rather than Los Angeles, and Texas's capital is Austin rather than Houston.

On the reading test an applicant may see Capital in a sentence such as "What is the capital of the United States?" or "Washington, D.C., is the capital." The Capitol building (with an o) sits in Washington and houses the chambers of the Senate and the House of Representatives, and the Capitol dome is one of the most recognizable images in American civic life. Distinguishing the two spellings is a common point of difficulty in vocabulary instruction but the reading test concerns the city-meaning spelling, capital.