sector

noun

• Section
• Zone (designated area).
• Part of a circle, extending to the center
• Fixed-sized unit (traditionally 512 bytes) of sequential data stored on a track of a digital medium (compare to block)
• An area designated by boundaries within which a unit operates, and for which it is responsible
• One of the subdivisions of a coastal frontier
• A fictional region of space designated for navigational or governance purposes.
• (calculation) an instrument consisting of two rulers of equal length joined by a hinge.
• A field of economic activity

  "public sector;  private sector"

• A toothed gear whose face is the arc of a circle.
• A fixed, continuous section of the track, such that sectors do not overlap but all sectors make up the whole track.