Hysteria, or somatization disorder, is a diagnostic label applied to a state of mind, one of unmanageable fear or emotional excesses. The fear is often centered on a body part, most often on an imagined problem with that body part (disease is a common complaint). People who are "hysterical" often lose self-control due to the overwhelming fear.
Because of its association with female hysteria the term hysteria fell out of favor in the latter half of the 20th century. The word "hysterical" was replaced with synonyms such as functional, nonorganic, psychogenic and medically unexplained. In 1980 the American Psychiatric Association officially changed the diagnosis of “hysterical neurosis, conversion type” to “conversion disorder.”