cos·​mo·​naut | \ ˈkäz-mə-ˌnȯt How to pronounce cosmonaut (audio) , -ˌnät\

Definition of cosmonaut

: an astronaut of the Soviet or Russian space program

Examples of cosmonaut in a Sentence

Recent Examples on the Web

And over the holiday weekend, intrigue grew as one of the Russian cosmonauts tasked with investigating the hole seemed to agree, according to the Associated Press. Avery Thompson, Popular Mechanics, "The ISS Hole Came From Inside the Station, Says Cosmonaut," 26 Dec. 2018 Repeatedly, mission control urged the hard-charging cosmonauts to take a break. Eric Berger, Ars Technica, "Russian cosmonauts spend nearly eight hours cutting into their spacecraft," 12 Dec. 2018 Anne McClain, Canadian astronaut David Saint-Jacques and Russian cosmonaut Oleg Kononenko. Seattle Times Staff, The Seattle Times, "Spokane astronaut reaches space station aboard Russian craft," 3 Dec. 2018 Among the other artifacts to be auctioned is the voice recorder from the first mission to carry a woman, Soviet cosmonaut Valentina Tereshkova. Robert Lee Hotz, WSJ, "Your Chance to Own a Piece of the Moon," 25 Nov. 2018 Joining him on the mission are NASA astronauts Scott Tingle and Drew Feustel, astronaut Norishige Kanai of the Japan Aerospace Exploration Agency, and cosmonauts Oleg Artemyev and Anton Shkaplerov of Russia's Roscosmos space agency. Tariq Malik,, "SpaceX Dragon Capsule Returns to Earth from Space Station," 5 May 2018 Less than two weeks ago, a Soyuz rocket took off with a Russian cosmonaut and a NASA astronaut riding in a Soyuz capsule. Eric Berger, Ars Technica, "NASA chief says agency plans to launch crew on Soyuz in December," 23 Oct. 2018 Early cosmonauts and astronauts like Yuri Gagarin and John Glenn made only ballistic re-entries to get back down to Earth. Joe Pappalardo, Popular Mechanics, "Ballistic Reentry: How Astronauts Survive a Failed Launch," 11 Oct. 2018 The institute is known for conducting long-term simulations of stays in space using both cosmonauts and ordinary people. Elizabeth Howell,, "Touring Where the Mars-500 'Astronauts' Pretended to Take a Red Planet Journey," 11 July 2018

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'cosmonaut.' 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 cosmonaut

1955, in the meaning defined above

History and Etymology for cosmonaut

Russian kosmonavt, from Greek kosmos + Russian -navt (as in aeronavt aeronaut)

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Last Updated

9 Feb 2019

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Time Traveler for cosmonaut

The first known use of cosmonaut was in 1955

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English Language Learners Definition of cosmonaut

: an astronaut in the space program of Russia or the former Soviet Union


cos·​mo·​naut | \ ˈkäz-mə-ˌnȯt How to pronounce cosmonaut (audio) \

Kids Definition of cosmonaut

: an astronaut in the space program of Russia or the former Soviet Union

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More from Merriam-Webster on cosmonaut

Rhyming Dictionary: Words that rhyme with cosmonaut

Spanish Central: Translation of cosmonaut

Nglish: Translation of cosmonaut for Spanish Speakers Encyclopedia article about cosmonaut

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