as·​tro·​naut | \ ˈas-trə-ˌnȯt How to pronounce astronaut (audio) , -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

There is one class of people who definitely should not be breaking out the bubbly this New Year's Eve: astronauts aboard the International Space Station. Jennifer Ouellette, Ars Technica, "The secret to champagne’s universal appeal is the physics of bubbles," 31 Dec. 2018 Ninomiya’s all-black ensembles underlined his inventive use of fabric, while Piccioli’s colorful nylon capes suggested ecclesiastical astronauts. Erik Maza, Town & Country, "The Reimagining of a Classic Moncler Jacket," 20 Nov. 2018 Each of the items is beyond adorable, and perfect for hanging out in your Dreamhouse, riding around in a pink convertible, or pursuing a career as a veterinarian/business executive/astronaut/rockstar. Zoë Weiner, Teen Vogue, "NCLA Launched a Collection of Barbie-Inspired Beauty Products," 16 Nov. 2018 But go to the moon and do that experiment, as astronaut David Scott did during Apollo 15, where there is no air resistance, and the Equivalence Principle is clear to see. James Geach, Scientific American, "Triple-Star Test Shows Einstein Was Right, Again," 5 July 2018 Slightly bigger than a basketball, the robot from the German Space Agency is meant to assist German astronaut Alexander Gerst with experiments., "Rocket delivers robot, ice cream, mice to space station," 3 July 2018 The vehicle will carry supplies for the astronauts on board the International Space Station. Loren Grush, The Verge, "Watch SpaceX launch thousands of pounds of cargo and experiments to the International Space Station," 5 Dec. 2018 But growing interest in the mental risks of space travel — which NASA lists as one of the biggest threats to astronauts — has spawned a wave of new research and technology. Stephen Ornes, Discover Magazine, "Want to be a Mars Astronaut? You'll Need the Proper Mindset," 16 Oct. 2018 That will have to be tested in actual space with actual astronauts. Sarah Scoles, WIRED, "The Floating Robot With an IBM Brain Is Headed to Space," 28 June 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

14 Mar 2019

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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 How to pronounce astronaut (audio) \

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

Comments on astronaut

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


to corrupt or become corrupted

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