extreme tiredness resulting from mental or physical exertion or illness

he was nearly dead with fatigue

weakness in metal or other materials caused by repeated variations of stress

metal fatigue

menial non-military tasks performed by a soldier, sometimes as a punishment

we're on cookhouse fatigues, sir

loose clothing, typically khaki, olive drab, or camouflaged, of a sort worn by soldiers on active duty

battle fatigues

cause (someone) to feel exhausted

they were fatigued by their journey

weaken (a metal or other material) by repeated variations of stress

the nails have become rusted through or fatigued