Dictionary.com
Thesaurus.com
Synonyms

impair

1 American  
[im-pair] / ɪmˈpɛər /

verb (used with object)

  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

verb (used without object)

  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.


impair British  
/ ɪmˈpɛə /

verb

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

    his hearing was impaired by an accident

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Related Words

See injure.

Other Word Forms

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

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”; 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. )

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

A blind couple from Scarborough have said they hope the story of their upcoming marriage can inspire other visually impaired people who are nervous about dating.

From BBC

A hearing earlier this week by the Medical Practitioners Tribunal Service ruled her fitness to practice was impaired and she should be struck off.

From BBC

His eyesight remains partially impaired, comparable to "looking through a telescope".

From BBC

"Climate change is increasing the frequency of hot nights, which may independently contribute to cardiovascular morbidity and mortality by impairing sleep and autonomic recovery," he said.

From Science Daily

But the current mood of investors seems to be to presume that software credits could be impaired until their performance can demonstrate otherwise.

From The Wall Street Journal