N: 1. 1660s, “that which causes weariness,” from French fatigue “weariness,” from fatiguer “to tire” (15c.), from Latin fatigare “to weary, to tire out,” originally “to cause to break down,” from pre-Latin adjective *fati-agos “driving to the point of breakdown,” with first half from Old Latin *fatis, which is of unknown origin but apparently related to affatim (adv.) “sufficiently” and to fatisci “crack, split.” The second half is the root of agere “to drive”.
Especially “the labors of military persons” (1776). Meaning “a feeling of weariness from exertion” is from 1719. Of metals or other materials under strain, from 1877.
2. Fatigue is different from drowsiness. Drowsiness is feeling the need to sleep. Fatigue is a lack of energy and motivation. Drowsiness and apathy (a feeling of not caring about what happens) can be symptoms that go along with fatigue.
3. Fatigue can be a normal and important response to physical activity, emotional stress, boredom, or lack of sleep. Fatigue is a common symptom, and it is usually not due to a serious disease. But it can be a sign of a more serious mental or physical condition. When fatigue is not relieved by enough sleep, good nutrition, or a low-stress environment, it should be evaluated by your doctor.
4. Dr Rupal Shah, a GP in south London, says tiredness is one of the most common complaints she sees in her surgery. “I see loads and loads of patients who complain of feeling exhausted, even though they’re sleeping well. Often it’s been going on for several months.”
At any given time, one in five people feels unusually tired, and one in 10 have prolonged fatigue, according to the Royal College of Psychiatrists. Women tend to feel tired more often than men.
“It’s unusual to find anything physically wrong. Most of the time, fatigue is linked with mood and the accumulation of lots of little stresses in life,” says Dr Shah.
S: 1. OED – http://www.etymonline.com/index.php?term=fatigue (last access: 14 June 2016). 2 & 3. NIH – https://www.nlm.nih.gov/medlineplus/ency/article/003088.htm (last access: 14 June 2016). 4. NHS – http://www.nhs.uk/Livewell/tiredness-and-fatigue/Pages/why-am-I-tired.aspx (last access: 14 June 2016).