Sector sounds like section, doesn't it? That's a good way to remember that a sector is a specific part of society or the economy, made up of similar elements — like the health care sector or the education sector.

Our most common use of the word sector refers to a society’s divisions. For example, our economy is divided into the private sector (privately-owned interests) and the public sector (government). Other than that, the word also has many technical applications in math and science. From the Latin verb secare, "to cut," sector was applied long ago to math as a section of a circle, which carried through to military language as "a circle around a headquarters."

Definitions of sector
  1. noun
    a particular aspect of life or activity
    “he was helpless in an important sector of his life”
    synonyms: sphere
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    a specialized sphere of knowledge
    type of:
    aspect, facet
    a distinct feature or element in a problem
  2. noun
    a social group that forms part of the society or the economy
    “the public sector
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    business, business sector
    business concerns collectively
    black economy
    a hidden sector of the economy where private cash transactions go unreported
    big business
    commercial enterprises organized and financed on a scale large enough to influence social and political policies
    type of:
    social group
    people sharing some social relation
  3. noun
    a portion of a military position
  4. noun
    a plane figure bounded by two radii and the included arc of a circle
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    type of:
    plane figure, two-dimensional figure
    a two-dimensional shape
  5. noun
    measuring instrument consisting of two graduated arms hinged at one end
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    type of:
    measuring device, measuring instrument, measuring system
    instrument that shows the extent or amount or quantity or degree of something
  6. noun
    the minimum track length that can be assigned to store information; unless otherwise specified a sector of data consists of 512 bytes
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    type of:
    computer memory unit
    a unit for measuring computer memory
Word Family

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