equator

Theequator is an imaginary line drawn on the Earth and spaced equally between the North and South Pole. (noun)

An example of the equator is the latitude of 0°.

See equator in Webster's New World College Dictionary

noun

an imaginary circle around the earth, equally distant at all points from both the North and South Poles: it divides the earth's surface into the Northern and Southern Hemispheres
a circle like this around any celestial body
any circle that divides a sphere or other body into two equal and symmetrical parts
celestial equator

See equator in American Heritage Dictionary 4

(ĭ-kwāˈtər)

noun

a. The imaginary great circle around the earth's surface, equidistant from the poles and perpendicular to the earth's axis of rotation. It divides the earth into the Northern Hemisphere and the Southern Hemisphere.
b. A similar great circle drawn on the surface of a celestial body at right angles to the axis of rotation.
The celestial equator.
A circle that divides a sphere or other surface into congruent parts.

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