Okla. Admin. Code § 365:10-11-2
The following words or terms, when used in this subchapter, shall have the following meaning, unless the context clearly indicates otherwise:
"Allowable expense" means any necessary, reasonable, and customary item of expense at least a portion of which is covered under at least one of the Plans covering the person for whom claim is made except where a statute requires a different definition. However, items of expense under coverage such as dental care, vision care, prescription drug or hearing aid programs may be excluded from the definition of allowable expense. A plan which provides benefits only for any such items of expense may limit its definition of allowable expense to like items of expense. When a Plan provides benefits in the form of services rather than cash payments, the reasonable cash value of each service rendered shall be deemed to be both an Allowable Expense and a benefit paid. The difference between the cost of a private hospital room and the cost of a semi-private hospital room shall not be deemed to be an "Allowable Expense," except for the period of time during which the patient's confinement to a private hospital room is deemed medically necessary in terms of generally accepted medical practice.
"Plan" includes the following:
(A) Group and nongroup insurance contracts and subscriber contracts;
(B) Uninsured arrangements of group or group-type coverage;
(C) Group and nongroup coverage through closed panel plans;
(D) Group-type contracts;
(E) The medical care components of long-term care contracts, such as skilled nursing care;
(F) The medical benefits coverage in automobile "no fault" and traditional automobile "fault" type contracts;
(G) Medicare or other governmental benefits, as permitted by law, except as provided in a state plan under Medicaid. That part of the definition of plan may be limited to the hospital, medical and surgical benefits of the governmental program; and
(H) Group and nongroup insurance contracts and subscriber contracts that pay or reimburse for the cost of dental care.
"Plan" does not include:
(A) Hospital indemnity coverage benefits or other fixed indemnity coverage;
(B) Accident only coverage;
(C) Specified disease or specified accident coverage;
(D) Limited benefit health coverage;
(E) School accident-type coverages that cover students for accidents only, including athletic injuries, either on a twenty-four-hour basis or on a "to and from school" basis;
(F) Benefits provided in long-term care insurance policies for non-medical services, for example, personal care, adult day care, homemaker services, assistance with activities of daily living, respite care and custodial care or for contracts that pay a fixed daily benefit without regard to expenses incurred or the receipt of services;
(G) Medicare supplement policies;
(H) A state plan under Medicaid; or
(I) A governmental plan, which, by law, provides benefits that are in excess of those of any private insurance plan or other non-governmental plan; or
(J) Disability income protection coverage.
"This plan" means that portion of the policy which provides the benefits that are subject to this subchapter.
Okla. Admin. Code § 365:10-11-2