sector sector /ˈsɛktɝ/

noun

1. () A plane figure bounded by two radii and the included arc of a circle  ( sector )
   a plane figure bounded by two radii and the included arc of a circle
   
2. () A social group that forms part of the society or the economy  ( sector )
   a social group that forms part of the society or the economy
    The public sector
   the public sector
   
3. () A particular aspect of life or activity  ( sphere , sector )
   a particular aspect of life or activity
    He was helpless in an important sector of his life
   he was helpless in an important sector of his life
   
4. Measuring instrument consisting of two graduated arms hinged at one end  ( sector )
   measuring instrument consisting of two graduated arms hinged at one end
   
5. (military) a portion of a military position  ( sector )
   (military) a portion of a military position
   
6. The minimum track length that can be assigned to store information; unless otherwise specified a sector of data consists of 512 bytes  ( sector )
   the minimum track length that can be assigned to store information; unless otherwise specified a sector of data consists of 512 bytes