impair

¹ American  

[im-pair] / ɪmˈpɛər /

verb (used with object)

• impairs,
  present (3rd person singular)
• impaired,
  past participle,  past
• impairing
  present participle

1. to make or cause to become worse; diminish in ability, value, excellence, etc.; weaken or damage.

   to impair one's health;

   to impair negotiations.

   Antonyms:

   repair

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verb (used without object)

• impairs,
  present (3rd person singular)
• impaired,
  past participle,  past
• impairing
  present participle

1. to grow or become worse; lessen.

noun

1. Archaic. impairment.

impair ² American  

[an-per] / ɛ̃ˈpɛr /

adjective

French.

1. noting any odd number, especially in roulette.

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impair British  

/ ɪmˈpɛə /

verb

1. (tr) to reduce or weaken in strength, quality, etc

   his hearing was impaired by an accident

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Synonym Usage

See injure.

Other Word Forms

Derived Forms

• impairer
  noun
• impairment
  noun
• nonimpairment
  noun
• preimpairment
  noun
• impairable
  adjective
• self-impairable
  adjective
• self-impairing
  adjective
• unimpairable
  adjective

Inflected Forms

Participles

• impairing
  present
• impaired
  past

Conjugated Forms

Present

• impair
  simple
• impairs
  simple
• have impaired
  perfect
• has impaired
  perfect
• am impairing
  progressive
• are impairing
  progressive
• is impairing
  progressive
• have been impairing
  perfect progressive
• has been impairing
  perfect progressive

Past

• impaired
  simple
• had impaired
  perfect
• was impairing
  progressive
• were impairing
  progressive
• had been impairing
  perfect progressive

Future

• will impair
  simple
• will have impaired
  perfect
• will be impairing
  progressive
• will have been impairing
  perfect progressive

Etymology

Origin of impair¹

First recorded in 1250–1300; Middle English empairen, empeiren “to make worse,” from Middle French empeirer, from em- im- ¹ + peirer “to make worse” (from Late Latin pējōrāre, verb derivative of Latin pējor “worse”; cf. pejoration)

Origin of impair²

First recorded in 1820–30; from French: literally, “odd,” from Latin impār “odd, unequal”; equivalent to im- ² ( def. ) + pair ² ( def. )

Explanation

If you make bad decisions in the morning after drinking coffee, you might conclude that caffeine tends to impair your judgment. When you impair something, you damage it or make it work poorly. The root of the verb impair traces back to the Latin word pejorare, meaning “to make worse,” and that’s still what happens if you impair something. Whether it’s communication, visibility, or your marriage prospects, if you impair it, you make it worse. The word can be used for situations that describe something that has deteriorated, such as “Snow continued to impair driving conditions.”

Example Sentences

See Examples For:

impair impairs impaired impairing

She said the scale, height, and mass of the new ballroom would impair her aesthetic, cultural, and historical interests in viewing and appreciating the White House.

From Slate ● Sep. 1, 2026

The committee typically engages such tools if a clear market-functioning or financial-stability risk threatens to impair monetary policy, a bar that current conditions don’t appear to meet.

From The Wall Street Journal ● Aug. 4, 2026

“Gondola cars encased in digital ads, flying 26 feet overhead every 25-30 seconds would irreparably impair the vista, and the sense of calm and escape from urban life,” wrote former state parks director Ruth Coleman.

From Los Angeles Times ● Aug. 1, 2026

Over time, these cysts can impair kidney function and eventually lead to kidney failure.

From Science Daily ● Jun. 17, 2026

All rulers of all ages have tried to impose a false view of the world upon their followers, but they could not afford to encourage any illusion that tended to impair military efficiency.

From "1984" by George Orwell

This damage impairs the ability of nerves to carry electrical messages from the brain to the rest of the body - including those needed for the precise control of muscles needed to walk.

From BBC ● Jul. 22, 2026

High blood sugar impairs immune function and narrows vessels that carry oxygen-rich blood, making it harder for skin to heal.

From Los Angeles Times ● Jun. 14, 2026

America’s current structural weakness against supply disruptions impairs its geopolitical position and gives U.S. adversaries a tempting target.

From MarketWatch ● Jun. 3, 2026

"We found that, contrary to popular belief, closing one's eyes actually impairs the ability to detect these sounds," said author Yu Huang.

From Science Daily ● Mar. 20, 2026

This blindness impairs us in every act of communication.

From "The Sense of Style" by Steven Pinker

"They let me take over for a while going down the straight because, being sight impaired, I couldn't see the bends. "

From BBC ● Sep. 5, 2026

TD says it doesn’t support the narrative that credit was an issue for the banks, since impaired provisions for credit losses fell and consumer delinquencies improved in the important unsecured category.

From The Wall Street Journal ● Sep. 2, 2026

Among first-generation offspring, signs of impaired glucose tolerance appeared only in males descended from mice that consumed sucralose.

From Science Daily ● Aug. 31, 2026

Riggs said the Teamsters’ safety argument is weakened by the inconsistent safety record of human truck drivers, who have fallen asleep at the wheel or driven while distracted or otherwise impaired.

From Los Angeles Times ● Aug. 29, 2026

In other words, if you are not hearing impaired, your ear will pick up and receive sounds.

From "Music and the Child" by Natalie Sarrazin

In implementing the law, the government further defined "harm" to include "significant habitat modification or degradation where it actually kills or injures wildlife by significantly impairing essential behavioral patterns, including breeding, feeding or sheltering."

From Barron's ● Jul. 10, 2026

Cedars-Sinai spokesperson Duke Helfand said the hospital would be unable to recruit and retain physicians, nurses, and specialists if the measure passed, dramatically impairing its ability to provide healthcare.

From Los Angeles Times ● Jun. 10, 2026

The longer these companies leave addictive, impairing features in place, the more plaintiffs they’ll create.

From The Wall Street Journal ● Apr. 1, 2026

“In particular, how effective drones are in impairing production and transportation of crude via the Strait of Hormuz.”

From MarketWatch ● Feb. 28, 2026

This is because the act of describing a face has the effect of impairing your otherwise effortless ability to subsequently recognize that face.

From "Blink" by Malcolm Gladwell

Related Words

• blunt
• damage
• debilitate
• decrease
• destroy
• diminish
• hurt
• lessen
• mar
• prejudice
• reduce
• spoil
• tarnish
• undermine
• weaken
• worsen