Answer:
It is a manifestation that is noted by an observer.
Explanation:
Symptoms are subjective while "signs" are objective.
For example, if a patient complains of a headache, body pain and dizziness, these are considered subjective because the observer cannot feel what he's feeling. Therefore, these are considered symptoms.
If the physician checks the patient's temperature and found it to be high (39°C), then this is now considered a sign because it is noted by an observer. Other examples of signs are: heart rate, pulse rate, urine output, etc.
