As used in this chapter, the term:

(1) "Employee" includes an officer of a political subdivision of the state. Any individual compensated for services as a school bus driver, either through a contractual relationship or otherwise, is deemed to be an employee of the governing board of education for which such services are performed.

(2) "Employee tax" means the tax imposed by Section 1400 of the federal Internal Revenue Code of 1939 and Section 3101 of the federal Internal Revenue Code.

(3) "Employment" means any service performed by an employee in the employ of the state or any political subdivision of the state, for such employer, except:

(A) Service which in the absence of an agreement entered into under this chapter would constitute "employment," as defined in the Social Security Act; or

(B) Service which under the Social Security Act may not be included in an agreement between the state and the secretary of health and human services entered into under this chapter. Service which under the Social Security Act may be included in an agreement only upon certification by the Governor in accordance with Section 218(d)(3) of the Social Security Act shall be included in the term "employment" if and when the Governor issues, with respect to such service, a certificate to the secretary of health and human services, pursuant to subsection (b) of Code Section 47-18-42.

(4) "Federal Insurance Contributions Act" means Subchapter A of Chapter 9 of the federal Internal Revenue Code of 1939 and Subchapters A and B of Chapter 21 of the federal Internal Revenue Code, as such codes have been and may from time to time be amended.

(5) "Political subdivision" means counties and incorporated municipalities and includes an instrumentality of: (A) the state, (B) one or more political subdivisions of the state, or (C) the state and one or more of its political subdivisions. Such term also includes the Board of Regents of the University System of Georgia, the Federal-State Cooperative Inspection Service of the State of Georgia, the Board of Trustees of Georgia Military College, and the Georgia Municipal Association.

(6) "Secretary of health and human services" includes any individual to whom the secretary of health and human services has delegated any functions under the Social Security Act, with respect to coverage under such act, of employees of states and their political subdivisions, and with respect to any action taken prior to April 11, 1953, includes the federal security administrator and any individual to whom such administrator had delegated any such functions.

(7) "Social Security Act" means the act of Congress approved August 14, 1935, Chapter 531, 49 Stat. 620, officially cited as the "Social Security Act," as such act has been and may from time to time be amended. Such term shall also include regulations and requirements issued pursuant to that act.

(8) "State agency" means the Employees' Retirement System of Georgia.

(9) "Wages" means all remuneration for employment, including the cash value of all remuneration paid in any medium other than cash; except that such term shall not include that part of such remuneration which, even if it were for "employment" within the meaning of the Federal Insurance Contributions Act, would not constitute "wages" within the meaning of that act.