For purposes of this Subchapter:
"Claimant" means the member or participating employer, or in the case of a deceased member a joint annuitant or beneficiary, filing an appeal with the System.
"System" means the Oklahoma Public Employees Retirement System, the Uniform Retirement System for Justices and Judges, the Oklahoma State Employees Deferred Compensation Plan, and the Oklahoma State Employees Deferred Savings Incentive Plan.
Okla. Admin. Code § 590:1-3-2