A person who is licensed to practice medicine and has trained at a school of medicine, chiropractic, optometry, podiatry, dentistry, or veterinary medicine, Same as doctor-fish, A practitioner of alternative medicine or folk medicine who does not have traditional medical credentials, intransitive verb_ To repair, especially in a makeshift manner; rig, To alter or modify for a specific end, To practice medicine, transitive verb_ To confer a doctorate upon; to make a doctor, Slang To tamper with and arrange for one's own purposes; to falsify; to adulterate