- fatigue (n.)
- 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 set in motion, drive; to do, perform" (see act (n.)).
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.
- fatigue (v.)
- 1690s, from French fatiguer "to tire" (15c.), from fatigue (see fatigue (n.)). Earlier in same sense was fatigate (1530s), from Latin fatigatus, past participle of fatigare. Related: Fatigued; fatiguing; fatigation (c. 1500).