Defect refers to : 1.An imperfection in a bodily system "visual defects"; "this device permits detection of defects in the lungs" 2.A failing or deficiency "that interpretation is an unfortunate defect of our lack of information" 3.An imperfection in an object or machine if there are any defects you should send it back to the manufacturer" While weakness means 1.A flaw or weak point 2.Powerlessness revealed by an inability to act "in spite of their weakness the group remains active" 2.The property of lacking physical or mental strength; liability to failure under pressure or stress or strain "his weakness increased as he became older"; "the weakness of the span was overlooked until it collapsed" and shorcoming is the synonyms of defect Demerit means 1.A mark against a person for misconduct or failure; usually given in school or armed forces "ten demerits and he loses his privileges" 2.The quality of being inadequate or falling short of perfection "they discussed the merits and demerits of her novel" cowboy...

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