de‧fect 1 / dɪˈfekt, ˈdiːfekt / noun [ countable ]
a fault or a lack of something that means that something or someone is not perfect :
All the cars are tested for defects before they leave the factory.
a genetic defect
COLLOCATIONS
ADJECTIVES/NOUN + defect
a serious defect The movie has a few serious defects.
a major defect (= very serious ) They have found a major defect in the program.
a slight/minor defect There are one or two minor defects on the car’s paintwork.
a physical defect Doctors examined the baby and could find no physical defects.
a structural defect Older buildings are bound to have some structural defects.
a genetic/inherited defect (= one that is passed to you in your genes ) The condition is caused by a genetic defect.
a birth defect (= one that you are born with ) About 11% of children have birth defects.
a heart defect Laura was born with a rare heart defect.
a speech defect (= an incorrect way of saying certain sounds ) He had a speech defect which made it quite difficult to understand him.
a character defect (= a fault in your character ) Laziness was just one of his character defects.
verbs
have a defect The old system had some serious defects.
correct a defect She had surgery to correct a defect in her right eye.
THESAURUS
something wrong
fault a problem in a machine, system, design etc that causes damage or makes it not work properly : The fire was caused by an electrical fault. | a fault in the engine
defect a fault in something such as a product or machine, resulting from the way it was made or designed : Cars are tested for defects before they leave the factory.
weakness a part of a plan, system, or argument that is not as good as the other parts, and makes it likely to fail : What are the strengths and weaknesses of each method?
flaw a fault in a plan, system, argument etc, especially one that makes it useless or not effective : Your argument has a fundamental flaw. | There was one major flaw in his suggestion – we didn’t have enough money.
bug a fault in a computer program : A bug in the system was quickly fixed.
glitch a small fault in the way something works, that can usually be easily corrected : I noticed a small glitch when installing the software.
mistake something that is wrong in someone’s spelling, grammar, calculations etc : The article was full of spelling mistakes.
there’s something wrong with something used when saying that there is a problem in a machine, car etc, but you do not know what it is : There’s something wrong with the computer – it won’t close down.
defect 2 / dɪˈfekt / verb [ intransitive ]
to leave your own country or group in order to go to or join an opposing one
defect to/from
a Russian actor who defected to the West
— defector noun [ countable ]
— defection / dɪˈfekʃ ə n / noun [ uncountable and countable ]