symptom

n. sign, indication, manifestation; something caused by and indicative of a certain disease or disorder

The term symptom (from the Greek  meaning 'chance', 'mishap' or 'casualty', itself derived from συμπιπτω meaning 'to fall upon' or 'to happen to') has two similar meanings in the context of physical and mental health:Strictly, a symptom is a sensation or change in health function experienced by a patient. Thus, symptoms may be loosely classified as strong, mild or weak. In this, medically correct, sense of the word, it is a subjective report, as opposed to a sign, which is objective evidence of the presence of a disease or disorder. Examples of symptoms are fatigue/tiredness, pain, or nausea. In contrast, elevated blood pressure, or abnormal appearance of the retina, would be a medical sign indicating the nature of the disease.A symptom may loosely be said to be a physical condition which indicates a particular illness or disorder (e.g. Longman, 1995). An example of a symptom in this sense of the word would be a rash. However, correctly speaking, this is known as a sign, as would any indication detectable by a person other than the sufferer without verbal information from the patient.
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Symptom /symp·tom/ any subjective evidence of disease or of a patient's condition, i.e., such evidence as perceived by the patient; a change in a [more]Symptom - Community and Resources

Noun
1. (medicine) any sensation or change in bodily function that is experienced by a patient and is associated with a particular disease
(hypernym) evidence, grounds
(hyponym) crepitation rale
(part-holonym) disease
(classification) medicine, medical specialty
2. anything that accompanies X and is regarded as an indication of X's existence
(hypernym) indication, indicant

n. symptom, sign, indication, manifestation of a disease or disorder