equatorial

[ee-kwuh-tawr-ee-uhl, ek-wuh-]

adjective

1. of, relating to, or near an equator, especially the equator of the earth.

2. of, like, or typical of the regions at the earth's equator.

   equatorial temperatures.

noun

1. a telescope mounting having two axes of motion, one parallel to the earth's axis and one at right angles to it.

2. Also called equatorial instrument. Also called equatorial telescope. a telescope with such a mounting.

equatorial

/ ˌɛkwəˈtɔːrɪəl /

adjective

1. of, like, or existing at or near the equator

2. astronautics (of a telescope) mounted on the perpendicular axes, one of which is parallel to the earth's axis

   an equatorial orbit

3. astronomy of or referring to the celestial equator

   equatorial coordinates

noun

1. an equatorial mounting for a telescope

Other Word Forms

• equatorially adverb
• nonequatorial adjective
• nonequatorially adverb
• transequatorial adjective
• transequatorially adverb
• unequatorial adjective

Word History and Origins

Origin of equatorial¹

First recorded in 1655–65; equator + -ial

Example Sentences

The authors compared their work with imagery of Mars in the equatorial southern highlands, which is heavily cratered but also full of valley networks.

Read more on Salon

Found in the warm, equatorial waters of the Indo-Pacific, heart cockles have a mutually beneficial relationship with microscopic algae that live inside their tissues.

Read more on Science Daily

During La Niña, unusually cold temperatures in the equatorial Pacific Ocean typically send winter storms on more northerly tracks, leaving the southern U.S. warmer and drier.

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Dr Klinger notes that space launches from equatorial regions – which may not require as much fuel – could mean that African space ports have an important role to play in the coming decades.

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Buzza said the launches are important for the Starlink satellite broadband network SpaceX is building, since they put the satellites into a polar orbit, complementing Florida launches that put them in an equatorial orbit.

Read more on Los Angeles Times