as·​tro·​naut | \ˈas-trə-ˌnȯt, -ˌnät\

Definition of astronaut 

: a person who travels beyond the earth's atmosphere also : a trainee for spaceflight

Examples of astronaut in a Sentence

Recent Examples on the Web

Both companies are currently developing spacecraft to take the NASA’s astronauts to and from the International Space Station. Loren Grush, The Verge, "NASA will review workplace safety at SpaceX and Boeing because Elon Musk smoked marijuana," 20 Nov. 2018 From there, GO Searcher will head for Cape Canaveral, Florida, where SpaceX teams will take the astronauts to a nearby airport for transport back to Houston. Eric Berger, Ars Technica, "Rocket Report: Kazakhstan picks SpaceX, SLS cost savings, Minuteman test," 9 Nov. 2018 One of those potential partner technologies has just been unveiled by Lockheed Martin, which is developing a lunar lander to take future astronauts to the surface of the moon. Avery Thompson, Popular Mechanics, "Lockheed Martin Unveils Design for Lunar Lander," 3 Oct. 2018 United Launch Alliance is also involved in NASA’s Commercial Crew program that will take American astronauts into space on missions launched from U.S. soil. James Rogers, Fox News, "NASA's Parker Solar Probe set to 'touch the Sun' on historic mission," 9 Aug. 2018 Grissom, a native of Mitchell, was one of America's first seven astronauts. Sarah Bahr, Indianapolis Star, "Ultimate Indiana bucket list: 50+ things to do in Indianapolis and around the state," 11 July 2018 Since the end of the shuttle program in 2011, NASA has contracted with the Russian space program to take astronauts on missions to the International Space Station. Steven Lemongello,, "'Space Force': Trump proposes new military branch," 18 June 2018 John Glenn, the first American astronaut to orbit the earth. Joshua Stewart,, "Trump suggests the military needs a new 'space force' military branch," 13 Mar. 2018 The three-engine rocket — bigger and more powerful than any booster since the Saturn V that took astronauts to the moon in the 1960s and 1970s — lifted off at 3.45 p.m. ET from Kennedy Space Center in Cape Canaveral, Florida. Mark Harris /, NBC News, "SpaceX's Falcon Heavy launch gives big boost to Elon Musk's Mars dream," 6 Feb. 2018

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

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First Known Use of astronaut

1928, in the meaning defined above

History and Etymology for astronaut

astr- + -naut (as in aeronaut)

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Statistics for astronaut

Last Updated

5 Dec 2018

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Time Traveler for astronaut

The first known use of astronaut was in 1928

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More Definitions for astronaut



English Language Learners Definition of astronaut

: a person who travels in a spacecraft into outer space


as·​tro·​naut | \ˈa-strə-ˌnȯt \

Kids Definition of astronaut

: a person who travels beyond the earth's atmosphere : a traveler in a spacecraft

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More from Merriam-Webster on astronaut

Rhyming Dictionary: Words that rhyme with astronaut

Spanish Central: Translation of astronaut

Nglish: Translation of astronaut for Spanish Speakers

Britannica English: Translation of astronaut for Arabic Speakers Encyclopedia article about astronaut

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