noun (n)

• any organization whose responsibility it is to defend against something

  adanya organisasi yang bertanggungjawab untuk mempertahankan terhadap sesuatu

  Example:
  Police are the major line of defense against crime.
  

  Synonym:
  line of defence
  

  source: wordnet30
• defensive structure consisting of a barrier that can be employed for defense against attack

  pertahanan struktur consisting dari penghalang itu boleh digunakan untuk pertahanan terhadap serangan

  source: wordnet30