1
: an imperfection or abnormality that impairs quality, function, or utility : shortcoming, flaw
carefully inspect a tire for defects
examined the porcelain for defects
a moral defect in his nature
neural tube defects
defects of metabolism
2
chemistry : an imperfection (such as a vacancy or an unlike atom) in a crystal lattice (see lattice sense 2)
defected; defecting; defects

intransitive verb

1
: to forsake one cause, party, or nation for another often because of a change in ideology
a former KGB agent who defected to America
2
: to leave one situation (such as a job) often to go over to a rival
the reporter defected to another network

Examples of defect in a Sentence

Noun They examine their products for defects. She was born with a heart defect. Vanity and pride were his two worst character defects.
Recent Examples on the Web
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Noun
Image In 2021, the South Korean authorities investigated Jeju Air after one of its planes flew despite having a defect, according to reports in the domestic news media. Choe Sang-Hun, New York Times, 29 Dec. 2024 Baby Kevin was born early, with a congenital heart defect. Nikki Battiste, CBS News, 14 Dec. 2024
Verb
Just consider if Georgia, Alabama, Auburn, Tennessee, LSU, Kentucky, Florida, Ole Miss and Mississippi State defected from the SEC, and the conference retooled with Troy, South Alabama, Georgia State and Southern Miss. Blake Toppmeyer, The Tennessean, 13 Sep. 2024 Dinner with Tiant After defecting from his native Cuba in 2009, Chapman met with Red Sox officials at Fenway Park to discuss a possible contract. Mac Cerullo, Boston Herald, 19 Dec. 2024 See all Example Sentences for defect 

Word History

Etymology

Noun

Middle English, borrowed from Latin dēfectus "failure, absence, lack, weakness," from dēficere "to be lacking, run short, weaken, fail" + -tus, suffix of action nouns — more at deficient

Verb

borrowed from Latin dēfectus, past participle of dēficere "to be lacking, fail, become disaffected, go over (to the side of an opponent)" — more at deficient

First Known Use

Noun

15th century, in the meaning defined at sense 1

Verb

1596, in the meaning defined at sense 1

Time Traveler
The first known use of defect was in the 15th century

Dictionary Entries Near defect

Cite this Entry

“Defect.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/defect. Accessed 5 Jan. 2025.

Kids Definition

: a lack of something necessary for completeness or perfection

defect

2 of 2 verb
: to desert a cause or party often in order to take up another
defection
-ˈfek-shən
noun

Medical Definition

: a lack or deficiency of something necessary for adequacy in form or function
a hearing defect

Legal Definition

: something or a lack of something that results in incompleteness, inadequacy, or imperfection: as
a
: a flaw in something (as a product) especially that creates an unreasonable risk of harm in its normal use see also latent defect
b
: an error or omission in a court document (as an indictment or pleading)
c
: some imperfection in the chain of title to property that makes the title unmarketable
defectively adverb
defectiveness noun

More from Merriam-Webster on defect

Last Updated: - Updated example sentences
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