Fatigue
Engineering definition
Progressive damage to a material evidenced by cracking and caused by cyclic stress or loading. Exposed to repeated stress, a material may lose resistance over time and fracture due to fatigue. In general, higher stress levels lead to earlier failure.
Medical definition
Exhaustion. Following mental strain, emotional distress, or physical exertion, symptoms of tiredness may be relieved by rest or sleep. Persistent fatigue may be a sign of poor physical condition or the onset of disease. It may also have a psychological cause.
Confusion
It may not be clear to a clinician that an engineer is describing a material property and not a person when s/he uses the term fatigue.
