Definition of impair in English:



  • Weaken or damage (something, especially a faculty or function)

    ‘a noisy job could permanently impair their hearing’
    • ‘Streaking and smearing impair vision and are caused by worn windshield wiper blades.’
    • ‘Cataracts are cloudy spots on the lenses of the eyes that impair vision.’
    • ‘It is true that tests on laboratory animals at very high doses suggest that these chemicals disrupt the nervous and immune systems, as well as impairing development and possibly affecting fertility.’
    • ‘Driving in an intoxicated state makes a person prone to accidents as alcohol impairs judgement and slows reflexes.’
    • ‘There has long been speculation that excessive accumulation of starch may impair chloroplast function.’
    • ‘High levels of the stress hormone cortisol appears to impair memory.’
    • ‘Scientists know from animal studies that damage to the amygdala impairs social functioning.’
    • ‘Retinal blood vessels can break down, leak, or become blocked, affecting and impairing vision over time.’
    • ‘Miners object to these devices because they are heavy to wear, block vision on the sides, get covered with dirt and grease, and scratch easily, drastically impairing vision.’
    • ‘A British study found that chronic jet lag causes the brain to shrink, impairing memory.’
    • ‘Beaming the laser on small areas of your skin basically destroys the hair follicle and impairs its growth.’
    • ‘His hair was plastered to his head and falling over his eyes, impairing his vision further.’
    • ‘Dehydration can impair the function of vital organs like the kidneys, brain, and heart.’
    • ‘Chronic inflammation can result in irreversible scarring of lung tissue, which impairs lung function.’
    • ‘It's your choice if you want to apply enough purple mascara to impair your vision.’
    • ‘The specific kinds of defect that I have traced to addiction are best understood as impairing our powers of reflective self-control, without depriving us of those powers altogether.’
    • ‘Free radicals are thought responsible for making cholesterol harmful to arteries and the heart and for impairing memory and movement with age.’
    • ‘Certain chemotherapy drugs can damage the pancreas and impair its ability to make insulin.’
    • ‘Taking too much daily zinc could also be a problem because, although it is not toxic, high doses can impair copper absorption.’
    damage, harm, diminish, reduce, weaken, lessen, decrease, blunt, impede, hinder, mar, spoil, disable
    undermine, compromise, threaten
    foul up, put the kibosh on
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Middle English enpeire, from Old French empeirier, based on late Latin pejorare (from Latin pejor worse). The current spelling is due to association with words derived from Latin beginning with im-.