There are "Doctors" of everything. Psychologists, nurse practitioners, audiologists, veterinarians, optometrists, pharmacists, chiropractors, and podiatrists hold professional medical doctorates. They aren't "Doctors." In the United States when people refer generally to "doctors" they mean physicians and surgeons with a Doctor of Medicine or Doctor of Osteopathic Medicine degree who are licensed to practice medicine.
When people say "Is there a doctor on the plane?" after someone has a hear attack they aren't looking for dentists or audiologists are they?
When people say "Is there a doctor on the plane?" after someone has a hear attack they aren't looking for dentists or audiologists are they?