impaired

impaired — adjective

1. Any ability, organ, or object that is impaired works less effectively than norma

1.adjectiveB2
Definition

Any ability, organ, or object that is impaired works less effectively than normal, typically because of injury, disease, or external damage — for instance, a person's hearing, memory, or the function of a machine can be impaired.

Example

After the accident, Bao's hearing was impaired in his left ear.

passive: be impaired by [cause/injury]

Constant dust in the factory had impaired the workers' lung function over time.

Common collocations
  • impaired vision
  • impaired hearing
  • impaired memory
  • impaired mobility
  • impaired judgement
  • impaired function
  • severely impaired
  • permanently impaired
Synonyms
  • weakened

    focuses on loss of strength rather than overall damage

  • damaged

    implies physical harm; stronger and more permanent than 'impaired'

  • reduced

    suggests a measurable lowering of ability, not necessarily damage

  • diminished

    more formal; suggests a gradual or partial decrease in function

Antonyms
  • unimpaired

    direct opposite; working at full capacity

  • intact

    suggests nothing has been harmed or reduced

Usage Note

Often used with body parts or bodily functions (vision, hearing, memory, mobility) in medical or technical contexts. The verb 'to impair' is transitive, but 'impaired' as an adjective describes a state or condition.

Common Mistakes

My phone is impaired.
My phone is damaged / broken.
'impaired' describes a reduction in function or effectiveness, not something that is completely broken or unusable.

2. A person described as impaired in a driving context cannot control a vehicle saf

2.adjectiveB2
Definition

A person described as impaired in a driving context cannot control a vehicle safely because their system contains alcohol, illegal drugs, or certain medicines. This is a formal legal term used in traffic law.

Example

A truck driver was arrested after tests showed he was impaired by alcohol.

passive: be impaired by [substance]

In Canada, driving with a blood alcohol level above 0.08 percent is legally impaired.

Common collocations
  • impaired driving
  • impaired driver
  • driving while impaired
  • impaired by alcohol
  • impaired by drugs
  • impaired by medication
Synonyms
  • intoxicated

    broader term covering any substance-based loss of control; also used medically

  • under the influence

    standard legal phrasing; often abbreviated as 'DUI' or 'DWI'

  • drunk

    informal and specific to alcohol; not used in formal legal documents

Antonyms
  • sober

    having no alcohol or drugs in the body; able to drive safely

Usage Note

Primarily used in legal or law-enforcement contexts. 'Impaired driving' is a specific criminal offence in many jurisdictions, often defined by a legal blood-alcohol limit. This sense rarely appears outside formal or official settings.

Common Mistakes

He felt impaired after two beers.
He was arrested for impaired driving.
This sense is formal and legal, describing a measurable inability to drive safely, not casual tipsiness.

Word family

Synonym discussion

Sense: adjective/1

All four words describe a reduction in quality or ability, but they differ in scope and connotation. 'Impaired' is the most neutral and technical term, suggesting a partial loss of function — often used for senses (vision, hearing) or cognitive abilities. 'Weakened' implies a loss of strength or power, typically physical, and sounds less clinical. 'Damaged' is stronger: it suggests actual harm or injury, potentially permanent, and applies to both physical objects (a damaged phone) and body parts (a damaged knee). 'Diminished' is more formal and often describes a gradual or comparative decrease (diminished returns, diminished capacity). For medical or psychological descriptions, 'impaired' is the preferred term; for everyday objects, 'damaged' sounds more natural.

impaired ↗weakeneddamageddiminished

Common collocations

Nouns

  • hearing impaired
  • visually impaired

Adverbs

  • severely impaired
  • seriously impaired
  • permanently impaired

Phrases

  • driving while impaired
  • impaired by alcohol or drugs

Prepositions

  • impaired by
  • impaired from

Etymology

LatinOld FrenchMiddle EnglishEnglish

Comes from Latin 'impeiorare', meaning 'to make worse' — a combination of 'in-' (into, onto) and 'peior' (worse). It passed into Old French as 'empeirer', then entered Middle English as 'empeiren' before the spelling shifted to 'impair' during the Renaissance period, influenced by Latin.