sector

[sek-ter] /ˈsɛk tər/
noun
1.
Geometry. a plane figure bounded by two radii and the included arc of a circle.
2.
a mathematical instrument consisting of two flat rulers hinged together at one end and bearing various scales.
3.
Machinery. a device used in connection with an index plate, consisting of two arms rotating about the center of the plate and set to indicate the angle through which the work is indexed.
4.
Military. a designated defense area, usually in a combat zone, within which a particular military unit operates and for which it is responsible.
5.
Astronomy. an instrument shaped like a sector of a circle, having a variable central angle and sights along the two straight sides, for measuring the angular distance between two celestial bodies.
6.
a distinct part, especially of society or of a nation's economy:
the housing sector; the educational sector.
7.
a section or zone, as of a city.
8.
Computers. a portion of a larger block of storage, as 1/128 of a track or disk.
verb (used with object)
9.
to divide into sectors.
Origin
1560-70; < Late Latin: sector, Latin: cutter, equivalent to of sec(āre) to cut + -tor -tor
Related forms
sectoral, adjective
subsector, noun
Examples from the web for sector
  • Health is one area in which the public sector consistently does a better job than the private sector at controlling costs.
  • For-profit colleges have been the fastest-growing sector of higher education for years.
  • sector allotment is based on past catches and where they were.
  • The private sector will end up with that same overhead eventually.
  • Much of the innovation reshaping our world comes from the private sector.
  • Some local entrepreneurs and their early employees are themselves refugees from the financial sector.
  • Higher education is a mammoth, diverse, and largely autonomous sector of society.
  • The disruptive reforms that have so changed the private sector should now be let loose on the public sector.
  • Until last week the situation had appeared to be calming, and rangers were hoping to re-enter the sector to track the gorillas.
  • In addition to the coal tax, the government also announced a number of financial incentives for the renewable energy sector.
British Dictionary definitions for sector

sector

/ˈsɛktə/
noun
1.
a part or subdivision, esp of a society or an economy: the private sector
2.
(geometry) either portion of a circle included between two radii and an arc. Area: 1/2r²θ, where r is the radius and θ is the central angle subtended by the arc (in radians)
3.
a measuring instrument consisting of two graduated arms hinged at one end
4.
a part or subdivision of an area of military operations
5.
(computing) the smallest addressable portion of the track on a magnetic tape, disk, or drum store
Derived Forms
sectoral, adjective
Word Origin
C16: from Late Latin: sector, from Latin: a cutter, from secāre to cut
Word Origin and History for sector
n.

1560s, "section of a circle between two radii," from Late Latin sector "section of a circle," in classical Latin "a cutter, one who cuts," from sectus, past participle of secare "to cut" (see section (n.)). Translated Greek tomeus in Latin editions of Archimedes. Meaning "area, division" appeared 1920, generalized from military sense (1916) of "part of a front," based on a circle centered on a headquarters. As a verb from 1884. Related: Sectoral; sectorial.

sector in Science
sector
  (sěk'tər)   
The part of a circle bounded by two radii and the arc between them.