The etymology of disease indicates the discomfort and inconvenience of the physical condition:
According to Wikipedia:
In many cases, terms such as disease, disorder, morbidity and illness are used interchangeably.3 There are situations however when specific terms are considered preferable.
Disease
The term disease broadly refers to any condition that impairs the normal functioning of the body. For this reason, diseases are associated with dysfunctioning of the body's normal homeostatic process.4 Commonly, the term disease is used to refer specifically to infectious diseases, which are clinically evident diseases that result from the presence of pathogenic microbial agents, including viruses, bacteria, fungi, protozoa, multicellular organisms, and aberrant proteins known as prions. An infection that does not and will not produce clinically evident impairment of normal functioning, such as the presence of the normal bacteria and yeasts in the gut, or of a passenger virus, is not considered a disease. By contrast, an infection that is asymptomatic during its incubation period, but expected to produce symptoms later, is usually considered a disease. Non-infectious diseases are all other diseases, including most forms of cancer, heart disease, and genetic disease.
Illness
Illness and sickness are generally used as synonyms for disease.5 However, this term is occasionally used to refer specifically to the patient's personal experience of his or her disease.[6][7] In this model, it is possible for a person to have a disease without being ill (to have an objectively definable, but asymptomatic, medical condition), and to be ill without being diseased (such as when a person perceives a normal experience as a medical condition, or medicalizes a non-disease situation in his or her life). Illness is often not due to infection, but a collection of evolved responses—sickness behavior by the body—that helps clear infection. Such aspects of illness can include lethargy, depression, anorexia, sleepiness, hyperalgesia, and inability to concentrate.[8][9][10]
Interestingly, the current use of the words, reverses the etymological implications with disease representing the objective nature, and illness representing the subjective experience of a malady.
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