Mo. Rev. Stat. § 87.120: Definitions.

The following words and phrases as used in sections 87.120 to 87.370, unless a different meaning is plainly required by the context, have the following meanings:

(1) "Accumulated contributions" , the sum of all amounts deducted from the compensation of a member and credited to his or her individual account in the members' savings fund together with interest thereon;

(2) "Actuarial equivalent" , a benefit of equal value when computed upon the basis of such mortality tables and interest rate as shall be adopted by the board of trustees;

(3) "Average final compensation" , the average earnable compensation of the member during his or her last two years of service as a firefighter, or if the firefighter has less than two years of service, then the average earnable compensation of his or her entire period of service;

(4) "Beneficiary" , any person in receipt of a retirement allowance or other benefit as provided by sections 87.120 to 87.370;

(5) "Benefit reserve" , the present value of all payments to be made on account of any retirement allowance or benefit in lieu of a retirement allowance upon the basis of such mortality tables and interest rate as shall be adopted by the board of trustees;

(6) "Board of trustees" , the board provided for in section 87.140 to administer the retirement system;

(7) "City" , any city not within a county and adopting the retirement system provided by sections 87.120 to 87.370;

(8) "Creditable service" , prior service plus membership service as provided in section 87.135;

(9) "DROP" , the deferred retirement option plan provided in section 87.182;

(10) "Earnable compensation" , the regular compensation which a member would earn during one year on the basis of the stated compensation for his or her rank or position;

(11) "Firefighter" , any officer or employee of the fire department of the city employed by the city for the duty of fighting fires, but does not include anyone employed in a clerical or other capacity not involving fire-fighting duties. In case of doubt as to whether any person is a firefighter within the meaning of sections 87.120 to 87.370, the decision of the board of trustees shall be final;

(12) "Medical board" , the board of physicians provided for in section 87.160;

(13) "Member" , a member of the retirement system as defined by section 87.130;

(14) "Membership service" , service as a firefighter rendered since last becoming a member;

(15) "Prior service" , all service as a firefighter rendered prior to the date the system becomes operative which is creditable in accordance with the provisions of section 87.135;

(16) "Retirement allowance" , annual payments for life which shall be payable in equal monthly installments or any benefits in lieu thereof granted to a member upon retirement or to a beneficiary;

(17) "Retirement system" , the firefighter's retirement system of any city as defined in section 87.125.