(1) The term “professional service” shall mean any type of personal service to the public which requires as a condition precedent to the rendering of the service the obtaining of a license or other legal authorization, and which, by reason of law, prior to June 7, 1969, could not be performed by a corporation. In addition, and by way of example without limiting the generality thereof, the personal services which come within this chapter are the personal services rendered by architects, certified or other public accountants, chiropodists, chiropractors, doctors of dentistry, doctors of medicine, optometrists, doctors of osteopathy, doctors of podiatric medicine, professional engineers, veterinarians, and, subject to the Rules of the Supreme Court, attorneys-at-law.

(2) The term “professional corporation” means a corporation which is organized and incorporated, under this chapter, for the sole and specific purpose of rendering a single professional service or qualified related professional services, and which has as its shareholders only individuals who themselves are duly licensed or otherwise legally authorized within this State to render the same professional service, or those component qualified related professional services, as the corporation.

(3) The term “qualified related professional services” means, and is limited to, any combination of the practice of medicine by doctors of medicine or doctors of osteopathy or both, and the practice of podiatry by doctors of podiatric medicine.