A doctor with a PhD is a doctor of what?

A doctor with a Ph.D. is commonly referred to as a doctor of philosophy. This does not necessarily mean that they specialize in the subject of philosophy itself but rather that they have achieved the highest level of academic education in their chosen field. The term "philosophy" in this context refers to the Greek word "philosophia," which translates to the love of wisdom. And in the academic realm, pursuing a Ph.D. means engaging in rigorous research, critical thinking, and the synthesis of knowledge, which aligns with the broader concept of philosophy. Therefore, a doctor with a Ph.D. is considered a doctor of philosophy, irrespective of their specific area of expertise.