A condition that may or may not involve clinical signs and symptoms that form a known disease entity.
Usually used synonymously with disease. Can be differentially defined by saying illness is present when an individual perceives himself as diseased and disease is present when identifiable by objective, external criteria.
A state of not being well.
Impairment of normal physiological function affecting part or all of an organism.
Sickness, disease, or poor health. Many factors determine a person’s susceptibility to illness. These include both genetic components and environmental influences. Although a person cannot control genetic predisposition, he or she can make intelligent decisions about diet, exercise, and habits such as smoking, drinking, and sexual activity. Proper lifestyle choices can help prevent many diseases. Doctors also recommend having regular checkups in order to diagnose illnesses as early as possible. For certain diseases, such as breast cancer or colon cancer, early detection can make a critical difference in outcome.
Illness refers to a person’s perception that they are not well, and it is a subjective sensation that may arise from both physical and psychological factors. Additionally, the term “illness” is also used to denote a disease or disorder.