defective

defective — adjective

1. describes an item, machine, or component that contains a fault which stops it fr

1.adjectiveB2
Definition

describes an item, machine, or component that contains a fault which stops it from operating correctly.

Example

The car manufacturer recalled over ten thousand defective airbags last month.

defective + product noun (airbags)

Christopher's laptop had a defective battery that would not hold a charge.

Common collocations
  • defective product
  • defective part
  • defective equipment
  • defective goods
  • defective component
  • defective system
Synonyms
  • faulty

    more common in everyday speech; 'defective' sounds more technical or formal

  • flawed

    suggests an imperfection that may or may not affect function; 'defective' implies it does not work

  • broken

    more informal and general; implies something is no longer in working condition

Antonyms
  • working

    simple opposite for everyday use

  • functioning

    formal opposite; suggests the item operates as expected

Grammar Patterns

defective + noun (product/part/equipment)

be + defective

Usage Note

Used for objects, machines, and systems — not for living beings in modern usage.

Common Mistakes

The plan was defective because it lacked detail.
The plan was deficient because it lacked detail.
'defective' is for things with a fault that do not work; 'deficient' is for things lacking enough of something.

2. describes a specific organ or bodily system that does not function normally, oft

2.adjectiveC1
Definition

describes a specific organ or bodily system that does not function normally, often because of damage or a condition present from birth.

Example

Damage to her eyes left Adaeze with defective vision that glasses could not fix.

defective + body function (vision)

The baby was born with a defective heart valve and needed surgery within days.

Common collocations
  • defective vision
  • defective hearing
  • defective heart valve
  • defective immune system
  • defective gene
Synonyms
  • impaired

    preferred in modern medical and respectful contexts; 'hearing-impaired' instead of 'defective hearing'

  • damaged

    suggests injury or harm rather than a congenital condition

  • abnormal

    broader; describes any departure from typical structure or function

Antonyms
  • healthy

    general opposite for body parts and systems

  • normal

    describes typical structure or function

Grammar Patterns

defective + body part/organ/system

be + defective in + body part

Usage Note

This sense usually describes a specific body part, organ, or system, not a person as a whole. Referring to a person as 'defective' is considered offensive in modern English. Use 'person with a disability' or specify the affected body part instead.

defective — noun

Word family

  • defect
    nounB2
  • defect
    verbB2
  • defectively
    adverbC1
  • defectiveness
    nounC1
  • defection
    nounC1

Synonym discussion

Sense: adjective/1

'Faulty' is the most common everyday word for something that does not work as intended, such as a faulty switch or a faulty machine. 'Flawed' suggests an imperfection that may or may not affect the function — a diamond can be flawed but still valuable, whereas a defective item cannot work correctly. 'Broken' is more general and informal, implying something has been damaged and no longer works, but does not necessarily imply an original manufacturing fault. 'Defective' carries a more technical or formal tone, often used in quality control, product safety, and legal contexts. For example: 'The faulty wiring caused the fire,' but 'The manufacturer recalled defective components.'

faultyflawed ↗broken ↗defective ↗

Common collocations

Nouns

Adverbs

Phrases

  • defective by design
  • defective in nature

Prepositions

Etymology

LatinFrenchEnglish

'Defective' comes from the Latin word 'defectivus', meaning 'lacking, wanting', which itself comes from 'deficere' — 'to desert, fail, or lack'. The word entered English through French in the 1400s, first describing things that were incomplete or imperfect. Its use for people with impairments appeared in the 1800s and is now considered offensive.