cosmonaut

noun

cos·​mo·​naut ˈkäz-mə-ˌnȯt 

-ˌnät

: an astronaut of the Soviet or Russian space program

Examples of cosmonaut in a Sentence

Recent Examples on the Web

The launch helped to propel a crew of three, including a NASA astronaut and two Russian cosmonauts, to the International Space Station for an eight-month stay. —Eric Lagatta, USA Today, 5 Dec. 2025

After all, the Soyuz MS-28 spacecraft carrying that trio — NASA astronaut Chris Williams and cosmonauts Sergey Kud-Sverchkov and Sergei Mikaev — docked with the orbiting lab safely that same day as planned. —Leonard David, Space.com, 4 Dec. 2025

The Soviet Union was dissolved while Russian cosmonaut Sergei Krikalev was on board the Mir space station in 1991. —Maham Javaid The Washington Post, Arkansas Online, 30 Nov. 2025

Once aboard, the trio will join NASA astronauts Mike Fincke, Zena Cardman and Jonny Kim, JAXA (Japan Aerospace Exploration Agency) astronaut Kimiya Yui and Roscosmos cosmonauts Sergei Ryzhikov, Alexey Zubritsky and Oleg Platonov. —Health Reporter, MSNBC Newsweek, 27 Nov. 2025

Word History

Etymology

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

First Known Use

1955, in the meaning defined above

Rhymes for cosmonaut

• aeronaut
• aforethought
• afterthought
• apricot
• argonaut
• astronaut
• camelot
• coffeepot
• concordat
• entrepot
• flowerpot
• huguenot

Kids Definition

cosmonaut

noun

cos·​mo·​naut ˈkäz-mə-ˌnȯt 

-ˌnät

: a Soviet or Russian astronaut