ecliptic

1 of 2

adjective

eclip·​tic i-ˈklip-tik How to pronounce ecliptic (audio)
: of or relating to the ecliptic or an eclipse

ecliptic

2 of 2

noun

: 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
After that, the Solar Orbiter will drift off the ecliptic plane to begin examining the sun’s poles. WIRED, 20 Sep. 2023 Right now, the comet is still on its way towards the outer reaches of the solar system, and is far below the ecliptic plane (the planets, including Earth, all orbit the sun on about the same geometric plane). Popular Science, 8 Aug. 2018 Every 173 days, for between 31 and 37 days, the Moon is lined-up perfectly to intersect the ecliptic—the apparent path of the Sun through our daytime sky. Jamie Carter, Forbes, 6 Feb. 2023 That orbit also lies on a plane, but it’s slightly tilted, about 5 degrees relative to the ecliptic plane. Brian McNoldy, The Conversation, 23 Apr. 2021 Part of the reason why we’re limited in our solar understanding is that scientists only have one good direction at which to look at the sun: the ecliptic plane. Darren Orf, Popular Mechanics, 10 Feb. 2023 Earth orbits the sun in a certain plane – it’s called the ecliptic plane. Brian McNoldy, The Conversation, 23 Apr. 2021 The main asteroid belt is in close alignment with the ecliptic plane, or the same plane that includes Earth’s orbit around the sun. Ashley Strickland, CNN, 6 Feb. 2023 Eclipses don’t happen every month because the Moon’s orbit of Earth is tilted by 5º to the ecliptic, so usually the New Moon is above or below the Sun and the full Moon is above or below Earth’s shadow. Jamie Carter, Forbes, 10 Nov. 2022
Noun
Solar eclipses occur because the moon’s orbital path intercepts what astronomers call the ecliptic—the apparent path the sun takes through our daytime sky. Jamie Carter, Forbes, 9 Feb. 2024 The moon’s orbital path is slightly inclined (by about 5º) to that ecliptic, intersecting it twice each month. Jamie Carter, Forbes, 9 Feb. 2024 That’s partly because, unlike the Voyager probes, New Horizons is flying close to the ecliptic—the plane of Earth’s orbit. Diane Hope, Ars Technica, 12 Dec. 2023 Since Mars is moving eastward along the ecliptic with about the same speed as the starry sky moves west from day to day (about four minutes due to Earth’s revolution around the sun), the time that Mars sets in the west is relatively consistently during February and March. Scientific American, 29 Jan. 2019 The Aquariids constellation is Aquarius, hence the shower’s name, and lies on the ecliptic, the sun’s path in the sky. Taylor Nicioli, CNN, 4 May 2023 The ecliptic also depicts the approximate monthly path of the moon in front of the zodiac. Paul Douglas, Star Tribune, 27 Sep. 2020 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

These examples are programmatically compiled from various online sources to illustrate current usage of the word 'ecliptic.' Any opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback about these examples.

Word History

Etymology

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

First Known Use

Adjective

14th century, in the meaning defined above

Noun

15th century, in the meaning defined above

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

Dictionary Entries Near ecliptic

Cite this Entry

“Ecliptic.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/ecliptic. Accessed 19 Mar. 2024.

Kids Definition

ecliptic

noun
eclip·​tic
i-ˈklip-tik
: the great circle of the celestial sphere on which the sun appears to move among the stars

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