[The area in the United States comprised of a 68 square mile area northeast of the Potomac River donated by the state of Maryland. The District of Columbia, also known as D.C., is not a state, nor is it part of any state. It is a "federal district" established by the US Constitution as the seat of government. The district is occupied entirely by the city of Washington. ( NCI )]
UMLS (NCI) C0012764