cos·mo·naut | \ˈkäz-mə-ˌnȯt, -ˌnät\

Definition of cosmonaut 

: an astronaut of the Soviet or Russian space program

Examples of cosmonaut in a Sentence

Recent Examples on the Web

Due to budgetary reasons, Roscosmos has reduced the number of cosmonauts on the International Space Station from three to two. Eric Berger, Ars Technica, "Russian editor: Our space program is entering the “Dark Ages”," 9 July 2018 Otherwise with Federatsiya stalled, Russian cosmonauts would depend on NASA to carry its crews to the near-lunar gateway and beyond. Anatoly Zak, Popular Mechanics, "Russia's Soyuz Spacecraft Could Find New Life as a Lunar Taxi," 6 July 2018 The Soviet Union, on the other hand, had a woman — Valentina Tereshkova — as its sixth cosmonaut 20 years ago., "June 19, 1983: Ride, Sally Ride," 19 June 2018 The Plain Dealer devoted a number of stories to the Soviet cosmonaut, detailing his 108-minute voyage and also his humble upbringing. John Petkovic,, "Yuri Gagarin, first man in space, still celebrated 57 years later (photos)," 12 Apr. 2018 In addition gazing at our tiny blue orb from a dizzying altitude of 250 miles, space tourists will have an opportunity for space walks accompanied by a professional cosmonaut. Anatoly Zak, Popular Mechanics, "Russia's Plan To Build a Luxury Hotel on the ISS," 21 Dec. 2017 In June 1963, Russian cosmonaut Valentina Tereshkova orbited Earth 48 times. NASA's Virtual Reality lab at the Johnson Space Center where astronauts come to train for EVA, Extravehicular activities. Alex Stuckey, Houston Chronicle, "Three of NASA's first female astronaut recruits speaking at Space Center Houston this week," 25 June 2018 Russian cosmonauts Anton Shkaplerov and Oleg Artemyev bring an official 2018 World Cup soccer ball on board the International Space Station to practice the world's game. Jim Reineking, USA TODAY, "FIFA World Cup: Top 10 best moments in tournament history," 8 June 2018 Feustel and fellow American astronaut Rick Arnold and Russian cosmonaut Oleg Artemyev aboard the Soyuz MS-08 were launched 1:45 p.m. Wednesday, according to WDIV-TV. Aleanna Siacon, Indianapolis Star, "Purdue astronaut Andrew Feustel among NASA crew heading to International Space Station," 21 Mar. 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.

See More

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)

Keep scrolling for more

Learn More about cosmonaut

Statistics for cosmonaut

Look-up Popularity

Time Traveler for cosmonaut

The first known use of cosmonaut was in 1955

See more words from the same year

Keep scrolling for more

More Definitions for cosmonaut



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 \

Kids Definition of cosmonaut

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

Keep scrolling for more

Comments on cosmonaut

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


not any or not one

Get Word of the Day daily email!

Test Your Vocabulary

Great Scrabble Words—A Quiz

  • scrabble-tiles-that-read-scrabble-quiz
  • Which of the following Q-without-U words means the number five in cards or dice?
True or False

Test your knowledge - and maybe learn something along the way.

Bee Cubed

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!