What does "zone" mean?

Zone: (Geog.) One of the five great divisions of the earth, with respect to latitude and temperature. Note: The zones are five: the torrid zone, extending from tropic to tropic 46º 56min, or 23º 28min on each side of the equator; two temperate or variable zones, situated between the tropics and the polar circles; and two frigid zones, situated between the polar circles and the poles. Commerce . . . defies every wind, outrides every tempest, and invades. Bancroft.

Additional senses

  1. 2.(Math.) The portion of the surface of a sphere included between two parallel planes; the portion of a surface of revolution included between two planes perpendicular to the axis. Davies & Peck (Math. Dict.)
  2. 3.(Nat. Hist.) (a) A band or stripe extending around a body. (b) A band or area of growth encircling anything; as, a zone of evergreens on a mountain; the zone of animal or vegetable life in the ocean around an island or a continent; the Alpine zone, that part of mountains which is above the limit of tree growth.
  3. 4.(Crystallog.) A series of planes having mutually parallel intersections.
  4. 5.Circuit; circumference. [R.] Milton. Abyssal zone. (Phys. Geog.) See under Abyssal. -- Zone axis (Crystallog.), a straight line passing through the center of a crystal, to which all the planes of a given zone are parallel.
  5. 6.To girdle; to encircle. [R.] Keats.

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