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Related to Neptunian: Uranian


 (nĕp′to͞on′, -tyo͞on′)
a. Roman Mythology The god of water, later identified with the Greek Poseidon.
b. The sea.
2. The eighth planet from the sun, having a sidereal period of revolution around the sun of 164.8 years at a mean distance of 4.5 billion kilometers (2.8 billion miles), a mean equatorial diameter of 49,528 kilometers (30,775 miles), and a mass 17.25 times that of Earth.

[Latin Neptūnus.]

Nep·tu′ni·an (-to͞o′nē-ən, -tyo͞o′-) adj.
American Heritage® Dictionary of the English Language, Fifth Edition. Copyright © 2016 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.


1. (Classical Myth & Legend) of or relating to the Roman god Neptune or the sea
2. (Geological Science) geology (of sedimentary rock formations such as dykes) formed under water


(Astronomy) of, occurring on, or relating to the planet Neptune
Collins English Dictionary – Complete and Unabridged, 12th Edition 2014 © HarperCollins Publishers 1991, 1994, 1998, 2000, 2003, 2006, 2007, 2009, 2011, 2014
References in periodicals archive ?
An exoplanet smaller than Neptune with its own atmosphere has been discovered in the Neptunian Desert around its star by an international collaboration of astronomers, with the University of Warwick taking a leading role.
It is the first of its kind, that is, the first exoplanet of its kind to have been found in the Neptunian Desert.
They found the huge rogue planet in the Neptunian Desert using the state-of-the-art Next-Generation Transit Survey observing facility.
barracks endless and the numbing cold, indulging our pleasures "Which god is associated with the adjective 'Neptunian'?" was a typical recent question, prompting the baffling but almost understandable answer "Er...
The cosmos wants you to do well and to prove it, out goes that unsettling alignment of Saturn, and Neptunian energy that's had you all over the place since 2015 in terms of your sense of self-worth, and the ups and downs around financial wellbeing, which were the work of planet Uranus moving these last eight years across Aries.
A limp Martian, Isela Poot saw, was too-pale Sinai tramp "Mila!" Oh, "Neptunian" is a Sinai nut pen, Ho!
They are mainly composed of ice and are thus called icy giant planets, or Neptunian planets.
the largest Neptunian moon, comprising more than 99.5% of
As the Zealian League continues on a destructive path toward a tyrannical reign, Jett soon realizes that the Neptunian's Water-breath may be the only thing that can change the game plan in an epic battle for supremacy.
The first-person narrative accounts for her knowledge of the Neptunian surroundings, saying "Tres ventanas abiertas confirman que el mar existe" (27).
Premature death is happening everywhere, but that does not seem to alter the routines of the inhabitants of the city of Tethys on the Neptunian moon called Triton.
The present-day narrator who is contacted by this future Neptunian experiences no discomfort or horror from the encounter, however.