Wherever used in this chapter, the following terms shall have the meanings hereinafter set forth or indicated, unless the context otherwise requires:

(a) "Association" means a voluntary unincorporated association of insurers formed for the purpose of enabling cooperative action to provide disability insurance in accordance with this chapter in this or any other state having legislation enabling the issuance of insurance of the type provided in this chapter.

(b) "Insurer" means any insurance company which is authorized to transact disability insurance in this state.

(c) "Extended health insurance" means hospital, surgical and medical expense insurance provided by a policy issued as provided by this chapter.