equatorial

adjective

Synonyms of equatorialnext
1
a
: 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
2
a
: 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

Examples of equatorial in a Sentence

a lush equatorial rain forest that is threatened by rampant development
Recent Examples on the Web
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
This year’s weather is also expected to be affected by El Nino, a natural warming of the equatorial Pacific that alters weather patterns and spikes temperatures across the globe. Tammy Webber, Chicago Tribune, 1 Aug. 2026 For example, El Niño's ultimate impacts depend on factors such as where the maximum heating takes place in the equatorial Pacific in the fall and early winter. Dinah Voyles Pulver, USA Today, 25 July 2026 SpaceX is also eyeing an equatorial orbit when Starship flies on the Artemis IV mission, and NASA may already be quietly shifting the mission's landing site to a higher latitude. Josh Dinner, Space.com, 23 July 2026 El Nino is a periodic warming of water in the central and eastern equatorial Pacific Ocean that can affect global weather patterns for months, according to Paul Pastelok, senior meteorologist with AccuWeather. Stephen Underwood, Hartford Courant, 20 July 2026 See All Example Sentences for equatorial

Word History

First Known Use

1664, in the meaning defined at sense 1a

Time Traveler
The first known use of equatorial was in 1664

Cite this Entry

“Equatorial.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/equatorial. Accessed 4 Aug. 2026.

Kids Definition

equatorial

adjective
equa·​to·​ri·​al ˌē-kwə-ˈtōr-ē-əl How to pronounce equatorial (audio)
ˌek-wə-
-ˈtȯr-
1
: of, relating to, or located at the equator
2
: of, originating in, or suggesting the region around the equator
equatorial heat

Medical Definition

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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