exo·​plan·​et | \ˈek-sō-ˌpla-nət, ˌek-sō-ˈpla-\

Definition of exoplanet 

: a planet orbiting a star that is not our sun

Examples of exoplanet in a Sentence

Recent Examples on the Web

So when scientists recently discovered the seven exoplanets of Trappist-1, NASA's visual artists had their work cut out for them. Sarah Scoles, WIRED, "The Case of the Evaporating Exoplanets," 12 Apr. 2018 Normally with an ordinary exoplanet, these objects diminish starlight in a very routine way. Loren Grush, The Verge, "Astronomers may have discovered the first moon ever found outside our Solar System," 3 Oct. 2018 Lawmakers also rejected Trump's plan to cancel the Wide-Field Infrared Survey Telescope (WFIRST), which would hunt exoplanets and dark matter. Lauren Morello, Scientific American, "U.S. Science Agencies Set to Win Big in Budget Deal," 22 Mar. 2018 The tool is based on a series of retro-futuristic exoplanet travel posters NASA released several years ago. Emily Matchar, Smithsonian, "NASA’s New Exoplanet Travel Bureau Lets You “Tour” Far-Distant Planets In 360 Degrees," 7 June 2018 Ranjan's work looking at early Earth coincides with his work in looking at planets beyond the solar system, also known as exoplanets. David Grossman, Popular Mechanics, "Sulfuric Volcanoes May Have Quickened Life on Earth," 9 Apr. 2018 The spacecraft aims to add thousands of exoplanets, or planets beyond our solar system, to the galactic map for future study. Washington Post, "NASA spacecraft aims to put mystery planets on galactic map," 15 Apr. 2018 Kepler has transformed what astronomers know about the number of exoplanets in the galaxy, but some worlds thought to be discovered may not be there after all. Avery Thompson, Popular Mechanics, "Some of Kepler's Discovered Planets Might Not Be Real After All," 11 May 2018 Of all the exoplanets, planets outside of Earth's solar system, discovered in recent years, one that's captured some of the most attention is Kepler-186f. David Grossman, Popular Mechanics, "Study Shows Exoplanet Has a Stable Axis Just Like Earth," 29 June 2018

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'exoplanet.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

See More

First Known Use of exoplanet

1992, in the meaning defined above

Keep scrolling for more

Learn More about exoplanet

Statistics for exoplanet

Last Updated

10 Dec 2018

Look-up Popularity

Time Traveler for exoplanet

The first known use of exoplanet was in 1992

See more words from the same year

More from Merriam-Webster on exoplanet

Britannica English: Translation of exoplanet for Arabic Speakers

Comments on exoplanet

What made you want to look up exoplanet? Please tell us where you read or heard it (including the quote, if possible).


amusing and light sparring with words

Get Word of the Day daily email!

Test Your Vocabulary

Late Autumn 2018 Words of the Day Quiz

  • frosted-autumn-leaves
  • Which is a synonym of yahoo?
Name That Thing

Test your visual vocabulary with our 10-question challenge!

Word Winder's CrossWinder

Test Your Knowledge - and learn some interesting things along the way.


Love words? Need even more definitions?

Subscribe to America's largest dictionary and get thousands more definitions and advanced search—ad free!