SYMPTOM, in medicine, is defined by Galen to be a preternatural affection which depends upon a disease or follows it. Thus symptoms are diseases produced by an original principal disease. But symptoms are sometimes the effect of symptoms also. A symptom may be a symptom and a disorder at the same time; as when a symptomatic fever is produced by a phlegmon.—A knowledge of the origin and cause of symptoms conduces to confirm the prognosis, and to the certain removal of the disease.