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

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

Dementia is an umbrella term for debilitating symptoms that can result in memory loss and impair movement and daily life.

From Barron's ● Jun. 15, 2026

Additional evidence from clinical guidelines and research on wound healing and glycemic control also points to the same conclusion: high blood sugar can impair immune function and slow tissue repair.

From Science Daily ● May 16, 2026

Southpaw Nakatani had wrestled back some control but was halted in his tracks when blood began to impair vision in his left eye following a clash of heads.

From BBC ● May 2, 2026

In the earlier discussion, however, I was referring to things that impair our ability to solve problems.

From "Blink" by Malcolm Gladwell

This impairs our ability to quickly shed excess heat and makes it harder to judge when our bodies are under burden, simply because we can't see as much sweat on our skin or clothing.

From BBC ● Jul. 8, 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

His mayoralty also offers today’s floundering New York the fundamental lesson that good government can make a city flourish, while bad government impairs it.

From The Wall Street Journal ● May 8, 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

Mice placed on a diet with 40% fewer calories, for instance, become more vulnerable to infections, reproduce less successfully, and show impaired growth.

From Science Daily ● Aug. 26, 2026

Because I am visually impaired, I dictate my thoughts, have AI convert them into written text, and then listen as it reads my words back so I can revise and edit.

From The Wall Street Journal ● Aug. 17, 2026

"Nowadays, if a visually impaired person is musically talented, they can pursue a career in music," she said.

From Barron's ● Aug. 13, 2026

If the Strait of Hormuz remains impaired and China continues restricting phosphate exports, nitrogen producers with secure, low-cost inputs should remain better positioned than phosphate producers dependent on imported sulfur.

From MarketWatch ● Aug. 1, 2026

His heart function remained impaired, though improved somewhat.

From "Class Matters" by The New York Times

When Calum MacDonald visited a bar in Laos he experienced "a blinding kaleidoscopic light" permanently impairing his vision, less than two days after having a drink.

From BBC ● Jul. 15, 2026

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

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