Doctor

Doctor: In a medical context, any medical professional with an MD, a PhD, or any other doctoral degree. The term doctor is quite nonspecific. A doctor may, for example, be a physician, psychologist, biomedical scientist, dentist, or veterinarian. In a nonmedical context, a professor of history might be addressed as doctor, an eminent theologian might be named a doctor of a church, and a person awarded an honorary doctorate by a college or university might also be called a doctor.

The word "doctor" comes from the Latin "docere" meaning to teach. A doctor was a teacher, especially a learned or authoritative one.