noun (n)

• a plane figure bounded by two radii and the included arc of a circle(noun.shape)

  source: wordnet30
• a social group that forms part of the society or the economy(noun.group)

  Example:
  The public sector.
  

  source: wordnet30
• a particular aspect of life or activity(noun.cognition)

  Example:
  He was helpless in an important sector of his life.
  

  Synonym:
  sphere
  

  source: wordnet30
• the minimum track length that can be assigned to store information; unless otherwise specified a sector of data consists of 512 bytes(noun.quantity)

  source: wordnet30
• a portion of a military position(noun.location)

  source: wordnet30
• measuring instrument consisting of two graduated arms hinged at one end(noun.artifact)

  source: wordnet30
• A part of a circle comprehended between two radii and the included arc.(noun)

  source: webster1913