Metaphors are figures of speech that derive from one context and are applied to another. For the book’s purposes, a metaphor is the application of conceptions and perceptions of illnesses (e.g., cancerous growths) to contexts outside of the relationship between the illness and the patient—for example, the way radical political groups are discussed as cancerous growths that need to be removed to stop their spread.  

In terms of medicine, etiology is the study of the causation of a disease or sickness. In this text it often serves that purpose; however, the term can also be used outside of medicine to explore the reasons for and causes of certain historical, mythological, or social developments.

A term that refers to the infliction or causation of punishment. Sontag often applies this word to social attitudes about cancer or tuberculosis diagnosis. It is a primary mode through which human history has understood the relation between the victim and the disease, which is to say that illness is often seen as a punishment for some sort of behavior.