From Longman Dictionary of Contemporary Englishimpairim‧pair /ɪmˈpeə $ -ˈper/ ●○○ verb [transitive] HARM/BE BAD FORSPOILto damage something or make it not as good as it should be The illness had impaired his ability to think and concentrate.► see thesaurus at harm→ See Verb table
Examples from the Corpus
impair• Making new memories is even more impaired.• Moreover, memory may be impaired for a variety of reasons, lack of initial attention is not the only possible explanation.• Cons: A great way to temporarily impair gastrointestinal processes to the discomfort of others.• The amount of alcohol he had drunk seriously impaired his ability to drive.• A lifetime spent with walking horses has permanently impaired his speech.• Profit figures become merely amounts which can be spent without impairing initial capital invested.• If a witness is allowed to withhold evidence, it impairs the legal process.• But as the subject's brain function becomes increasingly impaired these movements become more and more erratic.• Alcohol significantly impairs your ability to drive a car or operate machinery.• Treat it with respect through - hitting scenery and objects costs time, and eventually impairs your vehicle's performance.Origin impair (1300-1400) Old French empeirer, from Vulgar Latin impejorare, from Late Latin pejorare “to make worse” 