WebMD Symptom Checker is designed with a body map to help you understand what your medical symptoms could mean, and provide you with the trusted information you need to help make informed decisions. (Definition of illness from the Cambridge Advanced Learner's Dictionary & Thesaurus © Cambridge University Press) If you have an illness, there is something wrong with your health. An illness can last for a long time or a short time, and its effects can be serious or not serious. Illness represents a subjective experience of feeling unwell, often accompanied by suffering or discomfort. It signifies a deviation from an individual’s perceived normal state of health and well-being. Is there a difference between a disease and an illness? Technically, yes. A disease is something a physician can diagnose, and an illness is something you feel. The meaning of ILLNESS is sickness. A to Z list of common illnesses and conditions including their symptoms, causes and treatments. Explore comprehensive guides on hundreds of common and rare diseases and conditions from the experts at Mayo Clinic. In humans, disease is often used more broadly to refer to any condition that causes or can cause pain, dysfunction, distress, social problems, or death to the person affected, or similar problems for those in contact with the person. Find out what illness is going around in your area right now. Real-time tracking of norovirus, flu, RSV, COVID, and stomach bugs by state. Updated daily.