#weak_part__weak_spot__soft_spot  a place of especial vulnerability
  exclusion:  good_part
  supertype:  weakness  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"
  subtype:  Achilles'_heel  a seemingly small but actual mortal weakness
  subtype:  jugular  a vital part that is vulnerable to attack; "he always goes for the jugular"
  subtype:  underbelly  the quality of being weak or unprotected; "the soft underbelly of the Axis"- Winston Churchill

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