For the purposes of this chapter the following terms, unless a different meaning is plainly required by the context, shall have the following respective meanings:

(1) RETIREMENT SYSTEM. The Teachers' Retirement System of Alabama as defined in Section 16-25-2.

(2) PUBLIC SCHOOL. Any day school conducted within the state under the authority and supervision of a duly elected or appointed county or city board of education and any educational institution supported by and under the control of the state or any private nondenominational school operated nonprofit for the education of children of school age residing within a district where no public school is available for the children.

(3) TEACHER. Any teacher, principal, superintendent, supervisor, college professor, administrative officer, or clerk employed in any public school or public college within the state or employed in any private nondenominational school operated nonprofit for the education of children of school age residing within a district where no public school is available for the children or any similar employee or officer of the Department of Education or of the Alabama Education Association, or any attendance worker 50 percent or more of whose salary is paid from public school funds or any employee receiving a regular stated compensation from the retirement system. In all cases of doubt, the Board of Control shall determine whether any person is a teacher as defined in this chapter.

(4) SUPPORT PERSONNEL or EMPLOYEE. Any maid, custodian, adult bus driver, lunchroom or cafeteria worker, secretary, clerk, clerical assistant, maintenance worker, or other non-certificated employee who works an average of 20 hours weekly.

(5) EMPLOYER. The State of Alabama, the county school board, the city school board, the State Board of Education, or any governing body of any private nondenominational school operated nonprofit for education of children of school age residing within a district where no public school is available for the children or any other agency of and within the state by which a teacher is paid.

(6) MEMBER. Any teacher included in the membership of the system as provided in Section 16-25-3.

(7) BOARD OF CONTROL. The board provided for in Section 16-25-19 to administer the retirement system.

(8) MEDICAL BOARD. The board of physicians provided for in Section 16-25-19.

(9) TRUSTEES. The members of the Board of Control to administer the trust funds.

(10) SERVICE. Service as a teacher.

(11) PRIOR SERVICE. Service rendered prior to the date of establishment of the retirement system for which credit is allowable under Section 16-25-11.

(12) MEMBERSHIP SERVICE. Service as a teacher rendered while a member of the retirement system and on account of which contributions are made.

(13) CREDITABLE SERVICE. "Prior service" plus "membership service" rendered since last becoming a member.

(14) BENEFICIARY. Any person in receipt of a pension, an annuity, a retirement allowance, or other benefit as provided by this chapter.

(15) REGULAR INTEREST. Interest compounded annually at the rate determined by the Board of Control in accordance with subsection (b) of Section 16-25-20.

(16) ACCUMULATED CONTRIBUTIONS. The sum of all the amounts deducted from the compensation of a member and credited to his or her individual account in the annuity savings fund together with regular interest thereon as provided in Section 16-25-21.

(17) EARNABLE COMPENSATION. The full rate of the compensation that would be payable to a teacher if he or she worked the full normal working time. In cases where compensation includes maintenance, the Board of Control shall fix the value of that part of the compensation not paid in money. Earnable compensation shall not exceed the limitations imposed by Section 401(a)(17) of the Internal Revenue Code for public pension funds except that any employee who was a member of the Teachers' Retirement System before the first plan year beginning after December 31, 1995, shall not be subject to the earning limitations set forth in Section 401(a)(17). For Tier I plan members, the term earnable compensation for retirement purposes shall include overtime payments that are made to a member; however, earnable compensation shall not exceed 120 percent of any member's annual base compensation as certified by the employer. For Tier II plan members, earnable compensation shall include overtime payments that are made to the member but shall not include subsistence payments that are made to the member and shall not exceed one hundred twenty-five percent (125%) of the member's annual base compensation, as certified by the employer.

(18) AVERAGE FINAL COMPENSATION. For any Tier I Plan member, the average annual compensation of a teacher, with respect to which he or she has made contributions pursuant to paragraph b. of subdivision (1) of Section 16-25-21 during the three years in his or her last 10 years of creditable service for which the average is highest or during his or her entire period of creditable service if less than three years; except, that for any period prior to October 1, 1959, the compensation used in computing the average shall include compensation in excess of the maximum amount with respect to which members were required to contribute. For any Tier II Plan member, the average annual compensation of the member, with respect to which he or she has made contributions pursuant to paragraph b. of subdivision (1) of Section 16-25-21 during the five years in his or her last ten years of creditable service for which the average is highest or during his or her entire period of creditable service if less than five years.

(19) ANNUITY. Payments for life derived from the "accumulated contributions" of a member. All annuities shall be payable in equal monthly installments.

(20) PENSION. Payments for life derived from money provided by the employer. All pensions shall be payable in equal monthly installments.

(21) RETIREMENT ALLOWANCE. The sum of the "annuity" and the "pension."

(22) RETIREMENT. Withdrawal from active service with a retirement allowance or optional benefit in lieu thereof granted under this chapter.

(23) ANNUITY RESERVE. The present value of all payments to be made on account of any annuity or benefit in lieu of any annuity, computed upon the basis of the mortality tables as shall be adopted by the Board of Control, and regular interest.

(24) PENSION RESERVE. The present value of all payments to be made on account of any pension or benefit in lieu of any pension, computed upon the basis of the mortality tables as shall be adopted by the Board of Control, and regular interest.

(25) ACTUARIAL EQUIVALENT. A benefit of equal value, when computed upon the basis of the mortality tables as shall be adopted by the Board of Control, and regular interest.

(26) NORMAL CONTRIBUTION. The contributions of the state necessary to provide a pension equal to the annuity which the member's contribution made prior to age 65 with interest will provide at age of retirement not to exceed 65.

(27) TIER I PLAN. The defined benefit pension plan provided by the Retirement System to Tier I plan members.

(28) TIER II PLAN. The defined benefit pension plan provided by the Retirement System to Tier II plan members.

(29) TIER I PLAN MEMBER. Any member of the Retirement System who had service for which he or she received credit in the Teachers' Retirement System or in the Employees' Retirement System prior to January 1, 2013.

(30) TIER II PLAN MEMBER. Any member of the Retirement System who first began eligible employment with a Teachers' Retirement System or an Employees' Retirement System participating employer on or after January 1, 2013, and who had no eligible service in the Teachers' Retirement System or the Employees' Retirement System prior to January 1, 2013.