Meaning of “defect” - Learner’s Dictionary

defect

noun [ C ] us uk /ˈdiːfekt/

a fault or problem with someone or something:

a birth defect
A mechanical defect caused the plane to crash.
defective adjective us uk /dɪˈfektɪv/

having a fault or problem:

defective goods

(Definition of “defect noun” from the Cambridge Learner’s Dictionary © Cambridge University Press)