defectとは何ですか?The lack of something necessary or desirable for completion or perfection; a deficiency: a visual defect. An imperfection that causes inadequacy or failure; a shortcoming. See Synonyms at blemish.To disown allegiance to one's country and take up residence in another: a Soviet citizen who defected to Israel. To abandon a position or association, often to join an opposing group: defected from the party over the issue of free trade.