defect

American  

[dee-fekt, dih-fekt, dih-fekt] / ˈdi fɛkt, dɪˈfɛkt, dɪˈfɛkt /

noun

• defects
  plural

1. a shortcoming, fault, or imperfection: a defect in a machine.

   a defect in an argument;

   a defect in a machine.

2. lack or want, especially of something essential to perfection or completeness; deficiency: a defect of action.

   a defect of common sense

   a defect of action.

3. Also called lattice defect.  Also called crystal defect,.  Crystallography. a discontinuity in the lattice of a crystal caused by missing or extra atoms or ions, or by dislocations.

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verb (used without object)

• defects,
  present (3rd person singular)
• defected,
  past participle,  past
• defecting
  present participle

1. to desert a cause, country, etc., especially in order to adopt another (often followed by from orto ).

   He defected from the U.S.S.R. to the West.

defect British  

noun

1. a lack of something necessary for completeness or perfection; shortcoming; deficiency

2. an imperfection, failing, or blemish

3. crystallog a local deviation from regularity in the crystal lattice of a solid See also point defect dislocation

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verb

1. (intr) to desert one's country, cause, allegiance, etc, esp in order to join the opposing forces

Synonym Usage

Defect, blemish, flaw refer to faults that detract from perfection. Defect is the general word for any kind of shortcoming or imperfection, whether literal or figurative: a defect in eyesight, in a plan. A blemish is usually a defect on a surface, which mars the appearance: a blemish on her cheek. Flaw is applied to a defect in quality, caused by imperfect structure (as in a diamond) or brought about during manufacture (as in texture of cloth, in clearness of glass, etc.).

Other Word Forms

Derived Forms

• defectibility
  noun
• defector
  noun
• predefect
  noun
• redefect
  verb (used without object)
• defectible
  adjective
• defectless
  adjective
• nondefecting
  adjective

Inflected Forms

Nouns

• defects
  plural

Participles

• defecting
  present
• defected
  past

Conjugated Forms

Present

• defect
  simple
• defects
  simple
• have defected
  perfect
• has defected
  perfect
• am defecting
  progressive
• are defecting
  progressive
• is defecting
  progressive
• have been defecting
  perfect progressive
• has been defecting
  perfect progressive

Past

• defected
  simple
• had defected
  perfect
• was defecting
  progressive
• were defecting
  progressive
• had been defecting
  perfect progressive

Future

• will defect
  simple
• will have defected
  perfect
• will be defecting
  progressive
• will have been defecting
  perfect progressive

Etymology

Origin of defect

First recorded in 1375–1425; late Middle English, from Latin dēfectus “failure, weakness,” equivalent to dēfec-, variant stem of dēficere “to run short, fail, weaken” ( see deficient) + -tus suffix of verb action

Explanation

A flaw in something is a defect. At certain stores you can buy clothes with slight defects. You have to be careful because the defect can be minor, like a missing button, or major, like sleeves of uneven lengths. In a person, a defect is an imperfection, which can manifest itself mentally or physically. If you are diagnosed with a heart defect, you will have to seek the advice of specialists. A hearing defect might leave your dad deaf in one ear. If you are becoming forgetful, you can joke that you are developing a mental defect, but if it continues, you'll probably want to have your head examined.

Example Sentences

See Examples For:

defect defects defected defecting

The contract explicitly provided that she would terminate the pregnancy if the fetus had a serious birth defect and the intended parents requested an abortion.

From Slate ● Sep. 17, 2026

When a child has a congenital heart defect without other complications, the condition is classified as non-syndromic congenital heart disease.

From Science Daily ● Sep. 15, 2026

Ahmed and Gilkar had asked West to abort the pregnancy after a scan at 20 weeks showed the foetus had a severe heart defect.

From BBC ● Sep. 11, 2026

The Housing Ombudsman found Clarion had not handled the damp, mould and snagging issues appropriately even though the builder, Dandara, would still have been responsible during the defect period.

From BBC ● Sep. 4, 2026

Her husband dead, three children sold, the fourth defective, and her having to thank God for the defect.

From "Kindred" by Octavia Butler

This is not the first case in which a surrogate has refused to terminate a pregnancy after the intended parents learned that the fetus had serious birth defects.

From Slate ● Sep. 17, 2026

Together, the patient genetics and experimental findings pointed to the primary cilium as an important part of the process that may contribute to congenital heart defects.

From Science Daily ● Sep. 15, 2026

He also acknowledged that if the U.S. slows AI development alongside China, and the latter defects, it could lead to China’s geopolitical dominance.

From MarketWatch ● Sep. 14, 2026

Martin Boyd, from the charity, says that since the Grenfell fire, it has become clear that "the law is still stacked against the leaseholders who have a limited means of redress for building defects".

From BBC ● Sep. 8, 2026

“Everyone who defects has adjustment problems,” Ko Gyoung-bin, the director-general of Hanawon, told me when I visited the place.

From "Escape from Camp 14: One Man's Remarkable Odyssey from North Korea to Freedom in the West" by Blaine Harden

Kendall had been a key backer of Democrat Andrew Jackson in the 1828 election, having defected from Henry Clay’s Whigs.

From Slate ● Sep. 4, 2026

OpenAI took potshots at Apple in its filing, citing 400 employees who have defected from the iPhone-maker to join its ranks.

From The Wall Street Journal ● Sep. 1, 2026

Arabs within the SDF's ranks also defected en masse after Sharaa's army took control of two previously Kurdish-held provinces, Raqa and Deir Ezzor, leaving them at half their strength, according to Syria specialist Fabrice Balanche.

From Barron's ● Aug. 25, 2026

Montgomerie, who defected to Reform 18 months ago after a long career as a Tory adviser and commentator, has said he plans to appeal against the suspension.

From BBC ● Aug. 18, 2026

Later, Celia would learn with sadness that the girl had defected while on tour in Oaxaca and was playing a psychotic housewife on a popular Mexican novela.

From "Dreaming in Cuban" by Cristina García

He led Barnet Council from 2019 until 2022 before defecting to Reform in June 2025.

From BBC ● Sep. 15, 2026

It started with Navratilova, a record nine-time singles champion at the All England Club, who remained an inspiration to those back in her homeland after defecting from communist Czechoslovakia to the United States in 1975.

From BBC ● Jul. 11, 2026

The defecting lawmakers are making it heard that their decision wasn’t taken lightly.

From Salon ● Jan. 9, 2026

Mr. Pence and his board have set a target of $15 million from donors to finance the defecting analysts for three years, and as of Friday we hear they had raised more than $13 million.

From The Wall Street Journal ● Dec. 22, 2025

Common sense told him that telling lies and defecting from duty were sins.

From "Catch-22" by Joseph Heller

Related Words

• bug
• crack
• deficiency
• deformity
• error
• fault
• flaw
• glitch
• injury
• irregularity
• lack
• mistake
• shortage
• shortcoming
• weakness