The following words, as used in this chapter, unless the text otherwise requires or a different meaning is specifically required, shall mean:
"Board", the board of appeals on motor vehicle liability policies and bonds established in section 8A of chapter 26.
"Commissioner", the commissioner of insurance.
"Company", "insurance company" or "insurer", all corporations, associations, partnerships or individuals engaged as principals in the business of insurance.
Mass. Gen. Laws ch. 175E, § 1