[ ih-klip-tik ]
See synonyms for ecliptic on
  1. Astronomy.

    • the great circle formed by the intersection of the plane of the earth's orbit with the celestial sphere; the apparent annual path of the sun in the heavens.

    • an analogous great circle on a terrestrial globe.

  2. Astrology. the great circle of the ecliptic, along which are located the 12 houses and signs of the zodiac.

adjectiveAlso e·clip·ti·cal.
  1. pertaining to an eclipse.

  2. pertaining to the ecliptic.

Origin of ecliptic

1350–1400; Middle English <Medieval Latin eclīptica, feminine of eclīpticus<Greek ekleiptikós, equivalent to ekleíp(ein) (see eclipse) + -tikos-tic

Other words from ecliptic

  • e·clip·ti·cal·ly, adverb
  • non·e·clip·tic, adjective
  • non·e·clip·ti·cal, adjective
  • non·e·clip·ti·cal·ly, adverb
  • un·e·clip·tic, adjective
  • un·e·clip·ti·cal, adjective
  • un·e·clip·ti·cal·ly, adverb

Words Nearby ecliptic Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2023

How to use ecliptic in a sentence

  • The inclination of the plane of the satellites to the ecliptic is 98°, and the planet ascends almost in the plane of the ecliptic.

    Mysterious Psychic Forces | Camille Flammarion
  • Each station was assigned a uniform length of 13° 20' on the ecliptic, and a denomination, generally derived from mythology.

  • How many days will be required for it to move completely around the ecliptic from vernal equinox back to vernal equinox again?

    A Text-Book of Astronomy | George C. Comstock
  • If the obliquity of the ecliptic were made 10 greater, what would be the effect upon the seasons in the temperate zones?

    A Text-Book of Astronomy | George C. Comstock
  • The purpose of the signs of the zodiac is to show the position of the sun in the ecliptic at different times.

    Astronomical Lore in Chaucer | Florence M. Grimm

British Dictionary definitions for ecliptic


/ (ɪˈklɪptɪk) /

  1. astronomy

    • the great circle on the celestial sphere representing the apparent annual path of the sun relative to the stars. It is inclined at 23.45° to the celestial equator. The poles of the ecliptic lie on the celestial sphere due north and south of the plane of the ecliptic

    • (as modifier): the ecliptic plane

  2. an equivalent great circle, opposite points of which pass through the Tropics of Cancer and Capricorn, on the terrestrial globe

  1. of or relating to an eclipse

Derived forms of ecliptic

  • ecliptically, adverb

Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Scientific definitions for ecliptic


[ ĭ-klĭptĭk ]

  1. The great circle on the celestial sphere that represents the Sun's apparent path among the background stars in one year. The northernmost point this path reaches on the celestial sphere is the Tropic of Cancer, its southernmost point is the Tropic of Capricorn, and it crosses the celestial equator at the points of vernal and autumnal equinox.♦ The plane of the ecliptic is the imaginary plane that intersects the celestial sphere along the ecliptic, and the north and south ecliptic poles are the points where a perpendicular line through the middle of this plane intersect the sphere. The plane of the ecliptic corresponds to the plane in which the Earth orbits the Sun. If the Earth's axis were not tilted, the ecliptic would be identical to the celestial equator and the ecliptic poles identical to the celestial poles. In this case, the Sun's path would not move northward or southward from the equator during the year. As it is, the plane of the celestial equator is tilted 23.45° to the plane of the ecliptic, corresponding to the tilt of the Earth's axis with respect to its orbital plane, giving the Sun its apparent northward and southward movement among the background stars. See illustration at celestial sphere.

The American Heritage® Science Dictionary Copyright © 2011. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.