Definition of fatigue in US English:



  • 1Extreme tiredness resulting from mental or physical exertion or illness.

    ‘he was nearly dead with fatigue’
    • ‘But a critical distinction needs to be drawn between physical and mental fatigue.’
    • ‘The risk factors associated with unexplained fatigue were no different from those associated with cognitive symptoms or unexplained musculoskeletal complaints.’
    • ‘So often one hears of driver fatigue being the cause of extremely serious accidents.’
    • ‘The symptoms of this illness were excessive physical fatigue, inability to concentrate, and an unwillingness to eat or drink.’
    • ‘Caffeine prevents mental and physical fatigue by blocking receptors that notify the brain of low energy levels.’
    • ‘Even so, the job saps the vitality, and a referee gets mental fatigue as well as physical.’
    • ‘There are different kinds of fatigue associated with cancer therapies.’
    • ‘Symptoms of hepatitis include chronic fatigue and liver problems.’
    • ‘You should also be aware of the increased fatigue associated with this transition.’
    • ‘Other medical conditions can cause extreme fatigue or changes in appetite and sleep.’
    • ‘According to research, drivers aged under 30 are most likely to be affected by driver fatigue.’
    • ‘It is characterised by overwhelming mental and physical fatigue accompanied by a wide range of other symptoms.’
    • ‘Sleepiness and fatigue can affect physical and mental capabilities to perform at safe levels.’
    • ‘Eventually fatigue overtook my body, and I knew it was time to stop.’
    • ‘Two major causes of premature fatigue during exercise are dehydration and carbohydrate depletion.’
    • ‘Her first patient of the day was on thyroid replacement but continued to experience chronic fatigue and lack of energy.’
    • ‘A 75-year-old man was evaluated for unexplained chronic fatigue, lethargy, and weight loss.’
    • ‘Throughout the ordeal, Crystal experienced severe fatigue, nausea and weight loss.’
    • ‘Research shows that driver fatigue is a factor in approximately 25 % of all accidents on motorways and trunk roads.’
    • ‘This can cause a person to experience physical fatigue, along with mental fogginess, difficulty in concentrating, and dullness of the mind.’
    tiredness, weariness, exhaustion, overtiredness
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    1. 1.1 A reduction in the efficiency of a muscle or organ after prolonged activity.
      • ‘The remaining patients complained of leg fatigue as the predominant symptom limiting exercise.’
      • ‘Some patients could have stopped exercising due to nonventilatory reasons, such as leg muscle fatigue.’
      • ‘What are the best tests for assessing respiratory muscle fatigue?’
      • ‘Everything ached all of a sudden, muscle fatigue setting in at last from dragging Rob halfway around the city.’
      • ‘She cited severe leg fatigue as the reason for limitation of exercise.’
      • ‘Resistance to fatigue of this muscle group was also enhanced.’
      • ‘The frequency of frank respiratory muscle fatigue in acute asthma is unknown, but is probably low.’
      • ‘Clearly, these patients were limited in their exercise tolerance by fatigue of their muscles of ambulation.’
      • ‘Respiratory muscle fatigue develops when demand for energy exceeds the supply of energy.’
      • ‘The authors conclude that leg effort and fatigue of the quadriceps are infrequent after walking in patients with COPD.’
      • ‘This could make the inspiratory muscles vulnerable to the development of muscle fatigue.’
      • ‘Thus, in patients with severe airway obstruction, inspiratory muscle fatigue may limit exercise performance.’
      • ‘Subjects rated perceived symptoms of breathlessness and muscle fatigue at the end of the test.’
      • ‘The sensations of dyspnea and muscle fatigue were measured at rest and immediately after exercise on a 10-cm visual analog scale.’
      • ‘Glutamine helps to prevent muscle fatigue, thus allowing you to rip out more reps.’
      • ‘A key problem in many patients with respiratory failure requiring intubation is fatigue of respiratory muscles.’
      • ‘This study was not intended to investigate the cause of muscle fatigue in COPD.’
      • ‘Increased muscle creatine also buffers the lactic acid produced during exercise, delaying muscle fatigue and soreness.’
      • ‘In contrast, the increase in the sensation of muscle fatigue was high.’
      • ‘Acute pancreatitis and fatigue of the diaphragm muscle are also associated with damage caused by ROS.’
    2. 1.2with modifier A lessening in one's response to or enthusiasm for something, typically as a result of overexposure to it.
      ‘museum fatigue’
      • ‘Second, many of those voters develop election fatigue and begin to tune out much of the information.’
      • ‘Your senses become better attuned to art when the light is fresh; you are less subject to museum fatigue.’
      • ‘Even now a certain amount of election fatigue is beginning to set in.’
      • ‘Might the increase in the number of elections and referendums have induced election fatigue?’
      • ‘The Museo de las Culturas de Oaxaca is in a former monastery and a wander around the airy cloisters or in the excellent cacti garden offer a respite from any cases of museum fatigue.’
      • ‘How will the parties defeat election fatigue and boost declining turn-out numbers?’
      • ‘The news from Lone Star Park, Texas is that all is well, and that the local media, doubtless suffering from presidential election fatigue, is lapping her up.’
      • ‘He revealed a bit of fundraiser fatigue in response.’
      • ‘It's the sitting-down equivalent of museum/gallery fatigue, that special ailment of travellers everywhere.’
  • 2Weakness in materials, especially metal, caused by repeated variations of stress.

    ‘metal fatigue’
    • ‘Metal fatigue is one concern, damage incurred during liftoff is another.’
    • ‘However, we're close to the limit in terms of metal fatigue and durability.’
    • ‘The children don't know anything about metal fatigue, turbulence, and mid-air collisions.’
    • ‘If inappropriately sized, the fasteners can suffer metal fatigue leading to structural failure.’
    • ‘Nearly complete elimination of inclusions by vacuum melting produces a considerable increase in the transverse fatigue limit.’
    • ‘That along with corrosion and metal fatigue cased the bridge to fail.’
    • ‘The procedures for applying these methods of analysis to the determination of the fatigue limit have been well established.’
    • ‘It seems that the cause of the stirrup breaking was either metal fatigue or some manufacturing defect.’
    • ‘Sunlight provides the necessary heat, and metal fatigue and design imperfections make the tracks more malleable.’
    • ‘Engineers have also been looking at the threat of lightning, metal fatigue and noise.’
    • ‘Unfortunately, metal fatigue kept causing it to crash.’
    • ‘The spar had actually twisted as a result of metal fatigue and failure.’
    • ‘There is evidence of significant metal fatigue damage to the rails in the vicinity’
    • ‘Investigators said the fatigue cracks on the planes that crashed were confined to the wing structures.’
    • ‘The fatigue properties of metals are quite structure-sensitive.’
    • ‘Slip bands have been observed at stresses below the fatigue limit of ferrous materials.’
    • ‘But, the pistol is 62 years old, and metal fatigue sets in after a while.’
    • ‘Energy from the magnet is designed to elongate the atoms in the clubface, deterring metal fatigue and strengthening the face.’
  • 3fatiguesMenial non-military tasks performed by a soldier, sometimes as a punishment.

    • ‘When they were not performing work fatigues or training, soldiers were instructed during the time spent in the rear areas.’
    menial work, drudgery, chores, donkey work
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    1. 3.1 A group of soldiers ordered to perform menial, nonmilitary tasks, sometimes as a punishment.
  • 4fatiguesLoose-fitting clothing, typically khaki, olive drab, or camouflaged, worn by soldiers.

    ‘battle fatigues’
    • ‘We also used to wear gunnery qualification badges on our fatigues.’
    • ‘Seated next to me in the lounge was a group of soldiers dressed in battle fatigues.’
    • ‘She looked Indian, and had on green camouflage fatigues.’
    • ‘On the outskirts of town, soldiers in fatigues continued to focus on their search.’
    • ‘And he was wearing old army fatigues and combat boots.’
    • ‘The whole army was dressed in old British army fatigues from World War II, which gave the situation a surreal cinematic air.’
    • ‘The soldier had changed wardrobe and discarded his old army fatigues for good.’
    • ‘The figure is wearing military fatigues over a black shirt and a black and white checked scarf wrapped around his head.’
    • ‘He had on dark combat boots, green fatigues, and had a big black machine gun in his hand.’
    • ‘One evening in Cusco, a group of revolutionary militants clad in army fatigues came to the meeting.’
    • ‘The battery-operated doll comes complete with walkie-talkie and a wardrobe choice of military fatigues or bolero jacket and gold trousers.’
    • ‘She's become accustomed to the sound of fire engines and the sight of soldiers in fatigues searching vehicles.’
    • ‘Soldiers in camouflage fatigues and painted faces also carried heavy artillery to provide protective fire power in the event of a genuine security threat.’
    • ‘He is decked out with the standard dictatorial outfit of military fatigues and large cigar.’
    • ‘He turned to see a figure dressed in faded military fatigues.’
    • ‘When they finally parted 10 years later she was dressed in ‘military fatigues and working as an anthropologist on an Aboriginal island’.’
    • ‘After dinner, Roger appeared in military fatigues, complete with hat, sunglasses, jackboots, and swagger stick.’
    • ‘Dozens of young troops in military fatigues marched in formation and conducted a series of calisthenic drills and martial-arts exercises at an abandoned dirt lot.’
    • ‘Some of the soldiers' fatigues were splashed in blood and filth.’
    • ‘He was wearing his snug army t-shirt, baggy fatigues and combat boots.’
    khakis, camouflage clothing, camouflage gear
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[with object]
  • 1Cause (someone) to feel tired or exhausted.

    ‘they were fatigued by their journey’
    • ‘This considered, I felt slightly frustrated by the fact our opening league game was having to be played by pretty fatigued players.’
    • ‘But if you are fatigued, be prepared to face the reality that we are all overworked, overstressed and overbooked.’
    • ‘Keep your movement throughout each set continuous, then rest a normal amount of time (up to about a minute) between sets, even if you are not fatigued.’
    • ‘It doesn't make much sense to train hard when you are fatigued.’
    • ‘It doesn't matter who you are, how strong, how smart, how fast - if you get fatigued you are exponentially raising your chances of being in a car accident.’
    • ‘Try one, and you'll notice that you can become totally fatigued from just one exercise.’
    • ‘We were a bit fatigued before the quarter-final after all the hard training we have done.’
    • ‘I wasn't fatigued, of course; I actually was a very fit individual.’
    • ‘I simply tend to forget how fatigued normal people can become.’
    • ‘He was working nonstop and he was very fatigued.’
    • ‘It was either this or he was fatigued due to a long day and some inclement weather, which meant that he could not physically take this bend.’
    • ‘But if you are fatigued and have low energy, I think you can really affect how you feel by how you eat.’
    • ‘If you give up easily when you're fatigued, we'll notice that, too.’
    • ‘A headache like that can really fatigue a person.’
    • ‘It's true - you are unbelievably fatigued after one of his slow-count sessions and feel more than justified in taking the extra days to recover.’
    • ‘I was fatigued and all I wanted to do was get out of here.’
    • ‘There are other categories, but it fatigues me to list them.’
    • ‘So all of a sudden he is too fatigued to make the same tackle he made in the first half.’
    • ‘These are the same symptoms fatigued drivers face each minute longer they stay on the road than necessary.’
    • ‘I am always fatigued, my body shakes and sweats.’
    tire, tire out, exhaust, wear out, drain, make weary, weary, wash out, tax, overtax, overtire, jade, make sleepy
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    1. 1.1 Reduce the efficiency of (a muscle or organ) by prolonged activity.
      • ‘My only concern is that you find the ideal weight/rep combination that allows you to optimally fatigue the target muscle in the shortest time.’
      • ‘If you can do 12 reps without fatiguing your target muscles, increase the weight by 2-5 percent rather than doing additional reps.’
      • ‘Perform each exercise in perfect form with a weight heavy enough to fatigue the muscle in just a few repetitions.’
      • ‘Adding weight, like a medicine ball, to your exercises is an effective way to fatigue your muscles, he adds.’
      • ‘Doing more reps will only fatigue your muscles, which will decrease your speed and place you at greater risk for injury.’
      • ‘Just make sure you use weights that are heavy enough to fatigue your muscles after eight to 12 repetitions.’
      • ‘Remember, fatiguing the muscle isn't the point; building explosive power for optimal recruitment of fast-twitch muscle fibers is.’
      • ‘Muscle glycogen breakdown leads to lactic acid production, which fatigues the muscle.’
      • ‘Three well-planned exercises performed properly will always fully fatigue the triceps.’
      • ‘If you truly fatigue a muscle during your workout, then it should require about a week to recuperate adequately before training it again.’
      • ‘If I have a little bit of energy left at the end of my workout, I'll do something like a drop set for my shoulders and really fatigue the muscle.’
      • ‘In mild cases it may be necessary to fatigue the symptomatic muscle.’
      • ‘My legs are cramped and my muscles are fatigued.’
      • ‘Lifting heavier weights will tone your muscles while fatiguing them in the process.’
      • ‘Whereas only 1 of the 12 patients fatigued their quadriceps after an ISW, two thirds of the same patients did so after incremental cycling.’
      • ‘Do three sets of 15-20 reps with weights heavy enough to fatigue your muscles within the suggested rep range.’
      • ‘If your smaller muscles are fatigued, they can't provide the necessary help.’
      • ‘If your midsection muscles don't feel fatigued by the final rep of each set, your form may be to blame.’
      • ‘Do these exercises at the end of your regular strength-training workout because you will fully fatigue your abs performing these exercises.’
      • ‘Always use enough weight to fatigue your muscles by the final rep of each set.’
  • 2Weaken (a material, especially metal) by repeated variations of stress.

    • ‘It's steel, so it doesn't fatigue, rust or corrode.’
    • ‘Repeated stretching and sizing fatigues the brass to the point where it will eventually split, but I restrict things a little more.’
    • ‘Given the thin faces of today's drivers, how long does a driver last before the metal becomes fatigued?’
    • ‘For carbon forks in general, there should not be any limited life span, as carbon composites themselves are not subject to fatigue failures as metals are.’
    • ‘Have you ever bent a piece of metal back-and-forth until it fatigues and breaks?’


Mid 17th century (in the sense ‘task that causes weariness’): from French fatigue (noun), fatiguer (verb), from Latin fatigare ‘tire out’, from ad fatim, affatim ‘to satiety or surfeit’.