WikipediA:
"Doctor (title)
From Wikipedia, the free encyclopedia
This article is about the title of Doctor. For the article on Medical Doctors, see Physician.
"Dr." redirects here. For other uses, see DR (disambiguation).

Doctor, as a title, originates from the Latin word of the same spelling and meaning. The word is originally an agentive noun of the Latin verb docēre [dɔˈkeːrɛ] 'to teach'. It has been used as an honored academic title for over a millennium in Europe, where it dates back to the rise of the first universities. This use spread to the Americas, former European colonies, and is now prevalent in most of the world. Contracted "Dr" or "Dr.", it is used as a designation for a person who has obtained a doctorate-level degree. Doctorates may be research doctorates or professional doctorates.