Synonyms for Defective (same or very similar meaning)
WordNet sense 1 (having a defect):
faulty
WordNet sense 2 (not perfect; defective or inadequate):
imperfect
WordNet sense 3 (not normal; not typical or usual or regular or conforming to a norm):
abnormal
WordNet sense 4 (not working properly):
bad
WordNet sense 5 (not performing or able to perform its regular function):
nonfunctional, malfunctioning
From the ODE community, based on WordNet
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