Neptune

noun

Nep·​tune ˈnep-ˌtün How to pronounce Neptune (audio)
-ˌtyün
1
a
: the Roman god of the sea compare poseidon
b
: ocean
2
: the planet eighth in order from the sun see Planets Table
Neptunian adjective

Examples of Neptune in a Sentence

sailors shipwrecked by the wild waves of Neptune
Recent Examples on the Web
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
Many do have eccentricities close to 1; these likely come from long-period comets that originate out past Neptune. Phil Plait, Scientific American, 25 July 2025 For context, Neptune is 29 times farther from the sun than Earth. Jamie Carter, Forbes.com, 24 July 2025 The store was founded in 1973 by Gary Neptune, a Boulder mountaineer with several major ascents to his credit, including Mount Everest. John Meyer, Denver Post, 22 July 2025 On July 24th, the day of the lunation, Saturn retrograded in Aries, Neptune retrograded in Aries, Uranus in Gemini, and Pluto retrograde in Aquarius, are in aspect with the New Moon. Lisa Stardust, Refinery29, 21 July 2025 See All Example Sentences for Neptune

Word History

Etymology

Latin Neptunus

First Known Use

before the 12th century, in the meaning defined at sense 1a

Time Traveler
The first known use of Neptune was before the 12th century

Browse Nearby Words

Cite this Entry

“Neptune.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/Neptune. Accessed 29 Jul. 2025.

Kids Definition

Neptune

noun
Nep·​tune ˈnep-ˌt(y)ün How to pronounce Neptune (audio)
: the planet eighth in order from the sun see planet
Neptunian adjective

More from Merriam-Webster on Neptune

Last Updated: - Updated example sentences
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