The title "doctor" is traditionally used to refer to someone who has earned a Doctor of Medicine (MD) or Doctor of Osteopathic Medicine (DO) degree, or a Doctor of Veterinary Medicine (DVM) degree and is licensed to practice medicine. However, in some cases, the title "doctor" may also refer to individuals who have earned a Doctor of Nursing Practice (DNP) or a PhD in Nursing. In this case, the title "Doctor" would be an academic or professional title. Nurses who have not earned a doctoral degree are generally not referred to as "doctor." They are referred to by their specific nursing titles, such as Registered Nurse (RN) or Licensed Practical Nurse (LPN). However, some nurses may use the title "Dr." if they have earned a doctoral degree in nursing, or as an honorary title.