Definition: The PhD is a doctoral degree, specifically called a "doctor of philosophy" degree. This is misleading because PhD holders are not necessarily philosophers (unless they earned their degree in philosophy!). That said, PhD recipients are able to engage in thought experiments, reason about problems, and solve problems in sophisticated ways.
The PhD is awarded in all disciplines. Typically it requires several years of study beyond the master's degree. The exact number of years varies by discipline and by student. Some students complete in 4 years and others take up to 8 or more years of study depending on the field, the student's research topic, and the student's skills. Doctoral programs in some disciplines accept only applicants with master's degrees. Other programs accept students right out of college, permitting them to earn a master's as they go. Most PhD degrees require the completion of coursework, comprehensive exams, and adissertation
Also Known As: doctoral degree, doctor of philosophy