Symptom, n.
Etymology: [F. symptôme, Gr. pat to fly, to fall. See Syn-, and cf. Asymptote, Feather.]
1. (Med.)
Any affection which accompanies disease; a perceptible change in the body or its functions, which indicates disease, or the kind or phases of disease; as, the causes of disease often lie beyond our sight, but we learn their nature by the symptoms exhibited. Like the sick man, we are expiring with all sorts of good symptoms. Swift.
2. A sign or token; that which indicates the existence of something else; as, corruption in elections is a symptom of the decay of public virtue.
Syn. -- Mark; note; sign; token; indication.
Shades of meaning
Fernald has no entry of its own for symptom; he lists it under sign.
Where he writes about it:
A symptom is a vital phenomenon resulting from a diseased condition; in medical language a sign is an indication of any physical condition, whether morbid or healthy; thus, a hot skin and rapid pulse are symptoms of pneumonia; dulness of some portion of the lungs under percussion is one of the physical signs. — from sign