What is the causal study of disease typically called?

The causal study of disease is usually called pathology. Pathology is from the Ancient Greek meaning the study of suffering or life experience. It is a significant component of the causal study of disease, and it is a major field in modern medicine and diagnosis.

With a disease, it is often construed as a medical condition associated with specific symptoms and signs. It may be caused by external factors such as pathogens, or it may be caused by internal dysfunctions, such as autoimmune diseases. Diseases usually affect people not only physically, but also emotionally, as contracting and living with a disease can alter one's perspective on life, and one's personality.

The sense of the word pathology as a synonym of disease or pathosis is used very often in the field of health care. So, persistent usage of the word is now being actively downplayed (minimized). Modern pathology is concerned with it continuing to develop and act as a component in a distinct field of inquiry that studies disease.