Oedema the medical term for fluid retention lymphoedema chronic swelling caused by the lymphatic system not draining properly and other size related conditions of the legs ankles and feet affect many many people your mother and her mother before her might have known the condition as lsquodropsyrsquo or lsquohydropsyrsquo but whatever the name oedema is excess fluid in the spaces within the bodyrsquos tissues that causes uncomfortable swelling beneath the skin if this affe