376.891.  Definitions. — As used in sections 376.891 to 376.894, the following terms mean:

  (1)  "Certificate holder", a person who receives health care benefits or services pursuant to a policy, contract or plan;

  (2)  "Plan administrator":

  (a)  The person designated as the plan administrator by the instrument under which the contract or plan is operated; or

  (b)  If no plan administrator is designated, the plan sponsor;

  (3)  "Policy, contract or plan", a group insurance policy providing health care coverage on an expense incurred basis, a group service or indemnity contract issued by a not-for-profit health services corporation, a health maintenance organization plan or a self-insured group health benefit plan of any type or description.