equatorial

adjective

equa·​to·​ri·​al ˌē-kwə-ˈtȯr-ē-əl 

ˌe-kwə-

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

Synonyms

• low
• tropical

Examples of equatorial in a Sentence

a lush equatorial rain forest that is threatened by rampant development

Recent Examples on the Web

Ecuador specializes in roses; the cool mountain climate and consistent sunlight of its equatorial days are uniquely suited to producing straight-stemmed, big-blossomed flowers, highly sought after for celebratory bouquets. —Maryn McKenna, Scientific American, 13 Feb. 2025

That was despite the world shifting from the El Niño warming pattern — which helped make 2024 the world’s warmest year on record — and turning toward its cooler La Niña counterpart, which involves the cooling of equatorial Pacific waters, and can curb global temperatures. —Reuters, NBC News, 6 Feb. 2025

The big natural factor in global temperatures is usually the natural cycle of changes in the equatorial Pacific Ocean waters. —Seth Borenstein, Chicago Tribune, 6 Feb. 2025

Based on the results from this computer simulation, the team believes that Earth’s earliest dinosaurs likely emerged in a hot and dry equatorial region in the former supercontinent Gondwana. —Laura Baisas, Popular Science, 23 Jan. 2025

Word History

First Known Use

1664, in the meaning defined at sense 1a

Phrases Containing equatorial

• equatorial plane
• equatorial plate

Rhymes for equatorial

• categorial
• curatorial
• dictatorial
• directorial
• editorial
• immemorial
• infusorial
• janitorial
• professorial
• reportorial
• senatorial
• territorial

Kids Definition

equatorial

adjective

equa·​to·​ri·​al ˌē-kwə-ˈtōr-ē-əl 

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

equatorial

adjective

equa·​to·​ri·​al ˌē-kwə-ˈtōr-ē-əl  ˌek-wə- 

-ˈtȯr-

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