ecliptic

adjective
eclip·​tic | \ i-ˈklip-tik How to pronounce ecliptic (audio) \

Definition of ecliptic

 (Entry 1 of 2)

: of or relating to the ecliptic or an eclipse

ecliptic

noun

Definition of ecliptic (Entry 2 of 2)

: the great circle of the celestial sphere that is the apparent path of the sun among the stars or of the earth as seen from the sun : the plane of the earth's orbit extended to meet the celestial sphere

Examples of ecliptic in a Sentence

Recent Examples on the Web: Adjective Targets in intermediate ecliptic latitudes fall between those extremes. Lee Billings, Scientific American, 11 July 2022 That two planets can appear to almost collide is made possible by the fact that all the planets in the Solar System orbit the Sun on the same ecliptic plane. Jamie Carter, Forbes, 26 Apr. 2022 This reasoning eliminates any Lagrange points outside of this plane of the ecliptic (the imaginary plane containing Earth’s orbit around the sun). Manasee Wagh, Popular Mechanics, 29 Apr. 2022 The ecliptic is high in summer when the Sun rises in the northeast and sets in the northwest (meaning longer, hotter days) and low in winter when the Sun rises in the southeast and sets in the southwest (meaning shorter, colder days). Jamie Carter, Forbes, 7 Nov. 2021 Its position in the ecliptic—the plane of the Solar System—also provides a link to the Western zodiac. Jamie Carter, Forbes, 24 Jan. 2022 Using this high priority list as the input catalog, Kaltenegger is now working with NASA’s Transiting Exoplanet Survey Satellite (TESS) mission to search the ecliptic plan region for exoplanets. Jamie Carter, Forbes, 23 June 2021 Predicting the positions of the planets along the ecliptic was very difficult for early astronomers. Tony Freeth, Scientific American, 15 Dec. 2021 All star signs are signs of the zodiac—constellations on the ecliptic, a line in the sky that the Sun appears to follow. Jamie Carter, Forbes, 3 Sep. 2021 Recent Examples on the Web: Noun Only rarely does Mercury reach maximum elongation when the ecliptic is at a steep angle to the horizon, so that it can be spotted against a fairly dark sky. Geoff Gaherty, Scientific American, 30 Nov. 2012 The ecliptic is the plane of the solar system on which all the planets orbit the sun, and the moon travels nearby. Kristen Rogers, CNN, 27 Feb. 2020 Until now, almost all of the solar-watching spacecraft have orbited in the ecliptic, or the same plane that the planets travel around the sun. Kenneth Chang, New York Times, 10 Feb. 2020 The planets and the moon follow roughly the same path through the sky, which is called the ecliptic. Kristen Rogers, CNN, 27 Feb. 2020 By the modern definition, New Moon occurs when the Moon and Sun are at the same geocentric ecliptic longitude. Fox News, 21 Feb. 2020 This craft will spend the next two years performing fly-bys of Venus and Earth, using the gravity of both planets to kick itself into an unusual orbit that will take it well above the ecliptic, the plane in which all of the sun’s planets orbit. The Economist, 13 Feb. 2020 Mercury’s orbit is inclined seven degrees to the ecliptic, or plane of Earth’s orbit, as Bob King of Sky and Telescope explains. Brigit Katz, Smithsonian, 7 Nov. 2019 The moon would have formed in the plane of Earth’s equator, with its orbit also tilted far from the ecliptic. Simon J. Lock, Scientific American, 2 July 2019 See More

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

First Known Use of ecliptic

Adjective

14th century, in the meaning defined above

Noun

15th century, in the meaning defined above

History and Etymology for ecliptic

Adjective

Middle English ekliptik, borrowed from Latin eclīpticus, borrowed from Greek ekleiptikós, from ekleípein "to be obscured (of a celestial body)" + -t-, verbal adjective ending + -ikos -ic entry 1 — more at eclipse entry 1

Noun

Middle English ekliptik, borrowed from Medieval Latin eclīptica (short for eclīptica līnea "ecliptic line"), from feminine of Latin eclīpticus ecliptic entry 1; so called because eclipses occur on or near the ecliptic

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Time Traveler for ecliptic

Time Traveler

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

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Dictionary Entries Near ecliptic

eclipsis

ecliptic

ecliptical

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Statistics for ecliptic

Last Updated

15 Jul 2022

Cite this Entry

“Ecliptic.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/ecliptic. Accessed 9 Aug. 2022.

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More from Merriam-Webster on ecliptic

Britannica English: Translation of ecliptic for Arabic Speakers

Britannica.com: Encyclopedia article about ecliptic

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