Doctor is an academic title that 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 academic title in Europe since the 13th century, when the first doctorates were awarded at the University of Bologna and the University of Paris. Having become established in European universities, this usage spread around the world. Contracted "Dr" or "Dr.", it is used as a designation for a person who has obtained a doctorate (commonly a PhD/DPhil). In past usage, the term could be applied to any learned person. In many parts of the world today it is also used by medical practitioners, regardless of whether they hold a doctoral-level degree. Source: Wikipedia (en)