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.
The father and son are suspected of spying on Ukraine's Neptune anti-ship missile program. Shane Croucher, MSNBC Newsweek, 10 July 2025 Although the Capricorn full moon comes across as rather serious, there is a connection between Saturn—the ruling planet of Capricorn—and Neptune and Pluto, both retrograde, at the time of its occurrence. Danijela Pilic, Glamour, 10 July 2025 In recent months, Saturn put on a spectacular show for early risers, who witnessed the gas giant climb over the eastern horizon just ahead of sunrise, often in close proximity to Venus, Mercury and dimmer Neptune. Anthony Wood, Space.com, 9 July 2025 See Saturn, Neptune and the moon align Amateur astronomers can witness a rare alignment of planets and the moon in the early hours ahead of dawn on Wednesday, July 16. Hannah Poukish july 8, Sacbee.com, 8 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 20 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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