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

The two-minute trailer begins with a Soviet cosmonaut landing on the moon, and then gives a peek at how stateside astronauts will respond. Chloe Foussianes, Town & Country, "For All Mankind, a Show That Reimagines the Space Race, Is Coming to Apple TV," 3 June 2019 This sent the Soyuz spacecraft on a ballistic return trajectory to Earth that saved the lives of NASA astronaut Nick Hague and Russian cosmonaut Aleksey Ovchinin. Eric Berger, Ars Technica, "Two months after mishap, Russian Soyuz rockets back into space with crew," 3 Dec. 2018 But on October 11th, the vehicle suffered a catastrophic anomaly with two riders on board — NASA astronaut Nick Hague and Russian cosmonaut Aleksey Ovchinin. Loren Grush, The Verge, "Three astronauts will launch to space on Monday — two months after botched flight," 2 Dec. 2018 There was no particular threat to the team of American, Canadian astronauts and the Russian cosmonauts, but this just allows them to continue their focus on the scientific exploration, often through spacewalks. David Grossman, Popular Mechanics, "New Coating Keeps ISS Toilet Door Almost-Bacteria Free," 19 Mar. 2019 To leave the station would have required the departure of three astronauts and cosmonauts, because a Soyuz cannot depart without a full crew, as this would not leave enough seats for an emergency evacuation. Eric Berger, Ars Technica, "Russian theory that NASA sabotaged the space station spreading like wildfire," 12 Sep. 2018 Today, two Russian cosmonauts—Oleg Kononenko and Sergei Prokopyev—are taking an unprecedented spacewalk to find some answers. Avery Thompson, Popular Mechanics, "Watch Russian Cosmonauts Spacewalk to Find the Cause of a Mysterious ISS Leak," 11 Dec. 2018 The former cosmonaut—who also had a long career at one of Russia's primary aerospace contractors, RSC Energia—also criticized a rotating door of leadership at his old firm. Eric Berger, Ars Technica, "The old guard may be turning against the Russian space program," 4 Dec. 2018 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

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

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


incapable of being surmounted or overcome

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