This is the whole point- nobody knows what his real name is. Although he seems like an Earth person he is in fact a humanoid alien known as a Time Lord from the far-distant planet Gallifrey, which is very much bigger and infinitely more technically advanced than Earth. His native language is Gallifresian (although he speaks many alien languages), which has a completely different alphabet incomprehensible to Earth folk and may not be verbally pronounced at all, but communicated telepathically or via some other means. He goes by the name of 'The Doctor' to simplify matters to other life forms and to justify his brilliant genius in a whole wide range of areas. But nobody will ever know his real name- the series began in 1963 and ran till 1989, then was resurrected in 2005. Doctor Who is a genre that the BBC cannot afford to dispense with finally, so it can never run an episode where his real name is revealed.
The Doctor's name has never been revealed, and it probably never will be. Only few people within the story knew his real name - River Song was one of the few, as revealed in the first episode in which she appears. The Doctor goes by several pseudonyms, such as "John Smith", and others.
A doctors name plate is typically called a name tag. It is worn by the doctor, on top of their scrubs and has the name of the doctor and his/her title on it.
The abbreviation DO after a doctor's name stands for Doctor of Osteopathic Medicine.
Doctor of Osteopathy
An OD after a doctor's name refers to the individual being a doctor of optometry. These doctors are responsible for providing care for the eyes.
Abraham's doctor's name was the same as his name Abraham
Doctor Of Medicine
Colin Baker played the Doctor in 1993; however, the Doctors name is literally always the Doctor.
M.D. after a doctor's name stands for Doctor of Medicine.
The actors name is Matt Smith
the doctors name is jean grey (marvel girl)
Doctor of HYPnosis
It could stand for Doctor of Optometry, or Doctor of Osteopath.