What does "doctor" mean ?... all doctors are requested to read this. please..?

The word doctor derives from the Latin verb, docere, meaning to teach. So the term originally applied to any learned person, especially one who taught in a university. Later the term applied to those who achieved the highest degree the university offered, a doctorate. In academic settings, persons with these degrees, PhD, DSc, MD, JD, DMD or DDS, PsyD, OD, PharmD and many others are referred to as doctors. By custom in the USA at least, mainly doctors of medicine are called doctors outside the academic setting. But anyone who holds a doctorate is entitled to be addressed as such.