equa·tor | \ i-ˈkwā-tər , ˈē-ˌkwā- \

Definition of equator 

1 : the great circle of the celestial sphere whose plane is perpendicular to the axis of the earth

2 : a great circle of the earth or a celestial body that is everywhere equally distant from the two poles and divides the surface into the northern and southern hemispheres

3a : a circle or circular band dividing the surface of a body into two usually equal and symmetrical parts

b : equatorial plane the equator of a dividing cell

Examples of equator in a Sentence

Recent Examples on the Web

That’s when the sun appears to reach the Tropic of Cancer and then appears to retreat toward the equator. Blaine P. Friedlander Jr., Washington Post, "Skywatch: Saturn, Jupiter and Mars heading for opposition in June and July," 2 June 2018 Technically speaking, the equinox occurs when the sun is directly in line with the equator. Brian Resnick, Vox, "Summer is for meteor showers and stargazing. Here’s how to watch.," 22 June 2018 During that time, the North Hemisphere experiences the winter solstice, or the shortest day of the year, while those living south of the equator experience the longest day of the year. Madeline Farber, Fox News, "A guide to summer solstice, from Stonehenge to the earth's tilt," 21 June 2018 Nearer the equator, early elephants and antelope roamed Arabia’s grassy, wet interior, while North Africa was lushly forested where Saharan sand dunes drift today. Howard Lee, Ars Technica, "What happened last time it was as warm as it’s going to get later this century?," 18 June 2018 Last Friday morning, Alain Charmeau met with a handful of reporters at the Hotel des Roches in Kourou, the small town outside the European Space Agency's spaceport near the equator. Eric Berger, Ars Technica, "European rocket chief: Trump rhetoric strengthens our commitment to space," 2 July 2018 The satellite's lightweight ion propulsion system will slowly but efficiently boost the relay station into a circular orbit 22,300 miles above the equator. William Harwood, CBS News, "SpaceX rocket launches powerful communications satellite," 4 June 2018 But one subclass of the 3,000 or so satellites swarming around Earth is particularly useful: the 400 that pirouette around the planet at roughly 22,000 miles above the equator. NBC News, "Alien satellites might offer a new way to find E.T.," 19 Mar. 2018 The length of day and night are equal on the fall equinox, which is one of two annual equinoxes when the sun sits directly above the equator. Brigit Katz, Smithsonian, "Is the Fall Equinox the Secret to the Pyramids’ Near-Perfect Alignment?," 22 Feb. 2018

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'equator.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of equator

14th century, in the meaning defined at sense 1

History and Etymology for equator

Middle English, from Medieval Latin aequator, literally, equalizer, from Latin aequare

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Phrases Related to equator

the equator

Statistics for equator

Last Updated

6 Sep 2018

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Time Traveler for equator

The first known use of equator was in the 14th century

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More Definitions for equator


equa·tor | \ i-ˈkwā-tər \

Kids Definition of equator

: an imaginary circle around the earth everywhere equally distant from the north pole and the south pole


equa·tor | \ i-ˈkwāt-ər , ˈē-ˌ \

Medical Definition of equator 

1 : a circle or circular band dividing the surface of a body into two usually equal and symmetrical parts especially at the place of greatest width the equator of the lens of the eye

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Comments on equator

What made you want to look up equator? Please tell us where you read or heard it (including the quote, if possible).


the setting in which something occurs

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