astronaut

noun

as·​tro·​naut ˈa-strə-ˌnȯt 

-ˌnät

plural astronauts

: a person whose profession is to travel beyond the earth's atmosphere

NASA on Wednesday introduced the group of astronauts it has chosen for upcoming missions to the moon. The program, called Artemis, aims to send people back to the moon for the first time since the end of NASA's Apollo program in 1972.

—Kenneth Chang

broadly : any person who travels beyond the earth's atmosphere

William Shatner, the 90-year-old actor of "Star Trek" fame, endured a 10-minute, rocket-powered ride to the edge of space … . In that moment, at least one thing became certain: Yes, a nonagenarian can be an astronaut.

—Jackie Wattles

Word Icons

Examples of astronaut in a Sentence

Recent Examples on the Web

Williams will be accompanied by astronauts Sergey Kud-Sverchkov and Sergei Mikaev. —Health Reporter, MSNBC Newsweek, 27 Nov. 2025

He's been an astronaut and ice skater, and even donned a crown for the millennium in 2000. —Gillian Telling, PEOPLE, 27 Nov. 2025

This crew is made up of NASA astronauts Mike Fincke, Zena Cardman, and Jonny Kim, Japan Aerospace Exploration Agency (JAXA) astronaut Kimiya Yui, and Roscosmos cosmonauts Sergei Ryzhikov, Alexey Zubritsky, and Oleg Platonov. —Chris Young, Interesting Engineering, 27 Nov. 2025

These astronaut star projectors come in many varieties, but someone has decided this particular interstellar explorer needed a tiny electric guitar. —Chris McMullen, Space.com, 27 Nov. 2025

Word History

Etymology

astro- + -naut (in aeronaut)

Note: See note at astronautics.

First Known Use

1928, in the meaning defined above

Rhymes for astronaut

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

Kids Definition

astronaut

noun

as·​tro·​naut ˈas-trə-ˌnȯt 

-nät

: a traveler in a spacecraft

astronautic

ˌas-trə-ˈnȯt-ik

adjective

or astronautical

-i-kəl, 

-nät-

Etymology

from astro- "star, heavens" (derived from Greek astron "star") and -naut (derived from Greek nautēs "sailor," from naus "ship") — related to nausea, nautical see Word History at nausea