As used in sections 56.800 to 56.840, the following words and terms mean:

(1) “Annuity”, annual payments, made in equal monthly installments, to a retired member from funds provided for, in, or authorized by, the provisions of sections 56.800 to 56.840;

(2) “Average final compensation”, the average compensation of an employee for the two consecutive years prior to retirement when the employee’s compensation was greatest;

(3) “Board of trustees” or “board”, the board of trustees established by the provisions of sections 56.800 to 56.840;

(4) “Compensation”, all salary and other compensation payable by a county to an employee for personal services rendered as an employee, including any salary reduction amounts under a cafeteria plan that satisfies 26 U.S.C. § 125 or an eligible deferred compensation plan that satisfies 26 U.S.C. § 457 but not including reimbursement for any expenses, any consideration for agreeing to terminate employment, or any other nonrecurring or unusual payment that is not part of regular remuneration;

(5) “County”, the City of St. Louis and each county in the state;

(6) “Creditable service”, the sum of both membership service and creditable prior service;

(7) “Effective date of the establishment of the system”, August 28, 1989;

(8) “Employee”, an elected or appointed prosecuting attorney or circuit attorney who is employed by a county or a city not within a county;

(9) “Membership service”, service as a prosecuting attorney or circuit attorney after becoming a member that is creditable in determining the amount of the member’s benefits under this system;

(10) “Prior service”, service of a member rendered prior to the effective date of the establishment of the system^* which is creditable under section 56.823;

(11) “Retirement system” or “system”, the prosecuting attorneys and circuit attorneys’ retirement system authorized by the provisions of sections 56.800 to 56.840.