DEFENSE DEPARTMENT
Defense Department.An executive department of the federal government, responsible for
coordinating and overseeing military affairs and the agencies responsible for national security. •
The Department was established as the National Military Establishment in 1947, by combining the
War and the Navy Departments. Its name was changed to Department of Defense in 1949. The
Department’s components include the Army, the Air Force, the Navy, the Marine Corps, and the
Joint Chiefs of Staff. It is headed by the Secretary of Defense, who is answerable to the President
as Commander-in-Chief. — Also termed Department of Defense (abbr. DOD). [Blacks Law 8th]