Fatigue
Etymology
From French "fatigue," from Latin "fatigare" (to weary, tire out). Its military sense — "fatigues" as menial labor or work clothes — comes from the same root: the wearying chores soldiers were assigned.
noun · /fuh-TEEG/
A deep weariness of body or mind that rest does not readily fix.
What it names
Reach for it when ordinary tiredness fails to capture an exhaustion that lingers past a good night’s sleep.
Example
The fatigue from the illness lingered for weeks after the fever itself had gone.
Related idea
Fatigue differs from sleepiness: a sleepy person can fall asleep and wake refreshed, but a fatigued person feels drained even when not drowsy and often unrelieved by rest. That’s why chronic fatigue is a medical puzzle rather than a sleep problem.
noun · /fuh-TEEG/
The weakening or cracking of a material — especially metal — caused by repeated cycles of stress.
What it names
why a paperclip snaps after enough bending, or why aircraft parts are retired before they fail.
Example
The wing spar failed from metal fatigue after thousands of flights.
Related idea
Like erosion, it is damage that accumulates gradually rather than all at once.
noun (plural) · /fuh-TEEG/
Loose, hard-wearing clothing worn by soldiers, typically in camouflage.
What it names
the everyday work-and-combat uniform of the military.
Example
The recruits reported for drill in their fatigues.
Related idea
Named for the labor — “fatigue duty” — such clothing was originally issued for.