equa·​to·​ri·​al | \ ˌē-kwə-ˈtȯr-ē-əl How to pronounce equatorial (audio) , ˌe-kwə-\

Definition of equatorial

1a : of, relating to, or located at the equator or an equator also : being in the plane of the equator a satellite in equatorial orbit
b : of, originating in, or suggesting the region around the geographic equator
2a : being or having a support that includes two axles at right angles to each other with one parallel to the earth's axis of rotation an equatorial telescope mount
b : extending in a direction essentially in the plane of a cyclic structure (as of cyclohexane) equatorial hydrogens — compare axial

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Synonyms & Antonyms for equatorial


low, tropical



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Examples of equatorial in a Sentence

a lush equatorial rain forest that is threatened by rampant development

Recent Examples on the Web

The green belt of tropical rainforests that covers equatorial regions of the Americas, Africa, Indonesia and Southeast Asia is turning brown. Robin Chazdon, Quartz Africa, "Scientists are mapping out how to restore tropical rainforests around the world," 7 July 2019 That’s a complex weather pattern that starts in the equatorial Pacific and can end up influencing the weather worldwide, including hurricane seasons. Leigh Morgan, nola.com, "Hurricane season 2019: Here we go again," 29 June 2019 Instead, the quadcopter will explore the moon’s vast equatorial deserts, which are likely fed by a grab bag of material from all over the moon. Paul Voosen, Science | AAAS, "NASA will fly a billion-dollar quadcopter to Titan, Saturn’s methane-rich moon," 27 June 2019 Once there, Dragonfly will land in the equatorial region of the moon, which is covered by large sand dunes. Eric Berger, Ars Technica, "NASA will fund a revolutionary mission to fly through Titan’s atmosphere," 27 June 2019 Going from the beautiful Mediterranean coast through the Sahara Desert all the way down through the jungles in the equatorial region and then down into South Africa, and not a single sign of an individual country. Anchorage Daily News, "50 astronauts, in their own words," 23 June 2019 Cool Summer El Ninos occur as a warming equatorial Pacific spurs a reaction from the atmosphere, upsetting weather patterns across the globe. Bloomberg News, The Mercury News, "Forecast for El Nino’s ability to limit hurricanes this year is ‘murky’," 14 June 2019 El Niño, the climate phenomenon in the equatorial Pacific that often ushers in great ski seasons in the Rockies, was a boon for resorts all season long and has Colorado river rafters expecting a banner year. John Meyer, The Denver Post, "Colorado Ski Country USA projects record year thanks to consistent, extended snow season," 6 June 2019 It’s by far the largest planet in our solar system with an equatorial diameter of 88,000 miles, dwarfing our Earth’s 7,900 miles. Mike Lynch, Twin Cities, "Sky Watch: What’s big and round and almost on Earth’s doorstep? Jupiter, of course," 23 June 2019

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'equatorial.' 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 equatorial

1664, in the meaning defined at sense 1a

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Statistics for equatorial

Last Updated

13 Jul 2019

Look-up Popularity

Time Traveler for equatorial

The first known use of equatorial was in 1664

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English Language Learners Definition of equatorial

: of or relating to the equator : located at or near the equator


equa·​to·​ri·​al | \ ˌē-kwə-ˈtȯr-ē-əl How to pronounce equatorial (audio) , ˌe-kwə-\

Kids Definition of equatorial

: relating to or lying near the equator an equatorial climate


equa·​to·​ri·​al | \ ˌē-kwə-ˈtōr-ē-əl How to pronounce equatorial (audio) , ˌek-wə- How to pronounce equatorial (audio) , -ˈtȯr-\

Medical Definition of equatorial

1 : of, located at, or relating to an equator equatorial diameter
2 : extending in a direction essentially in the plane of a cyclic structure (as of cyclohexane) equatorial hydrogen atoms — compare axial sense 2b

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Comments on equatorial

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


something desired as essential

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