§ 215.2 Definitions.
As used in this part:
(a) Agency means each of the executive agencies and military departments (as defined in 5 U.S.C. 105 and 102, respectively) and the United States Postal Service; and in addition, for city or county withholding purposes only, all elements of the judicial branch.
(b) City means any unit of general local government.
(1) Which:
(A) Is classified as a municipality by the United States Bureau of the Census, or
(B) Is a town or township which, in the determination of the Secretary of the Treasury,
(i) Possesses powers and performs functions comparable to those associated with municipalities,
(ii) Is closely settled, and
(iii) Contains within its boundaries no incorporated places as defined by the United States Bureau of the Census; and
(2) Within the political boundaries of which five hundred or more persons are regularly employed by all agencies of the Federal Government.
(c) City income or employment taxes means any form of tax for which, under a city ordinance:
(1) Collection is provided by imposing on employers generally the duty of withholding sums from the pay of employees and making returns of the sums to a designated city officer, department, or instrumentality; and