For the purpose of this subchapter—

(1) “Government” means the Government of the United States;

(2) “agency” means an Executive agency and the Library of Congress, but does not include a Government controlled corporation;

(3) “employee” means an employee in or under an agency and more specifically defined by regulations prescribed by the President;

(4) “United States”, when used in a geographical sense, means the several States and the District of Columbia;

(5) “continental United States” means the several States and the District of Columbia, but does not include Alaska or Hawaii; and

(6) “foreign area” means—

(A) the Trust Territory of the Pacific Islands; and

(B) any other area outside the United States, the Commonwealth of Puerto Rico, the Canal Zone, and territories and possessions of the United States.