Hypochondriasis: The belief and fear of serious illness which lasts for six months, beyond and despite medical reassurance. Hypochondriacs were once viewed unsympathetically as comical figures in the way Moliere depicted them in his classic (1673) play "Le Malade Imaginaire" (The Imaginary Invalid). Hypochondriasis is now generally recognized to be a psychiatric disorder. This disorder is characterized by a preoccupation with body functions and by the interpretation of normal body sensations such as sweating and minor abnormalities such as aches as major problems of medical importance. Hypochondriasis usually begins in the teen-age years and young adulthood. Its onset is sometimes associated with an experience in which someone close, often a loved one, becomes seriously ill or dies.
The hypochondrium is the anatomic area of the upper abdomen just below (Greek "hypo" meaning "below") the cartilage (Greek "chondros" meaning "cartilage") of the ribs. Hypochondriasis was thought by the ancients to be due to disturbed function of the spleen and other organs in the upper abdomen.
Hypochondriasis may also be called hypochondria, hypochondriasm, or hypochondriacal neurosis. See also: Medical school syndrome.