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 trio will join NASA astronauts Jessica Meir, Jack Hathaway and Chris Williams, European Space Agency astronaut Sophie Adenot and Roscosmos cosmonauts Sergei Kud-Sverchkov, Sergei Mikaev and Andrei Fedyaev. — ABC News, 14 July 2026

They’re joined by cosmonauts Sergei Zalyotin and Alexander ‘Sasha’ Lazutkin, NASA officials, aerospace engineers, and numerous family members. — Jeff Spry, Space.com, 14 July 2026

Yes, Star City is a For All Mankind spinoff, telling the Soviet side of the alternate-history space race in which a cosmonaut is the first to walk on the moon. — Sophie Brookover, Vulture, 10 July 2026

Luke Delaney, Canadian Space Agency astronaut Joshua Kutryk and Roscosmos cosmonaut Sergey Teteryatnikov. — Richard Tribou, The Orlando Sentinel, 9 July 2026

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