Disease

A lack of ease, from des- "without, away" (see dis-) + aise"ease" (see ease).
Diseases can be mainly somatic, or psychological. Diseases that are a pathology of the psyche are a psychopathology.
Psychopathology is e.g. Narcissism—which is a sociopathy or lacking empathy for other beings (social empathy).
Diseases are stressors often resulting in fatality.
Some diseases are Unidentified—Unidentified diseases, or haven't been solved—Unsolved diseases; such as Chronic Chemical Sensistivity.