16 CFR § 456.1 - Definitions.
(a) A patient is any person who has had an eye examination.
(b) An eye examination is the process of determining the refractive condition of a person's eyes or the presence of any visual anomaly by the use of objective or subjective tests.
(c) Ophthalmic goods are eyeglasses, or any component of eyeglasses, and contact lenses.
(d) Ophthalmic services are the measuring, fitting, and adjusting of ophthalmic goods subsequent to an eye examination.
(e) An ophthalmologist is any Doctor of Medicine or Osteopathy who performs eye examinations.
(f) An optometrist is any Doctor of Optometry.
(g) A prescription is the written specifications for lenses for eyeglasses which are derived from an eye examination, including all of the information specified by state law, if any, necessary to obtain lenses for eyeglasses.