A physician is a person who practices biological medicine. See that article for more info/p>
In the United States, the term physician is commonly used to describe all medical doctors (as well as doctor). In Britain, Ireland, Canada, Australia, New Zealand, Japan, South Africa, India, Indonesia, Republic of China (Taiwan), Pakistan, Bangladesh, Sri Lanka, Zimbabwe and Hong Kong, the term doctor is prevalent (and in formal/legal contexts, medical practitioner as well), as physician refers to specialists in internal medicine. Not all physicians have doctorates, although they are still popularly called 'doctors'.