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

Solar storms produce space weather that can irradiate astronauts and people in planes, disrupt satellites’ electronics and drag their orbits down and even affect the electrical grid and cell phone coverage. —Sarah Scoles, Scientific American, 10 Dec. 2025

Lego Technic Planet Earth and Moon in Orbit A Lego solar system will be a hit with space nerds, future astronauts, and anyone who knows science is actually cool. —Jeaneen Russell, PEOPLE, 10 Dec. 2025

Finally, unlike with the ILRS, countries that sign the Artemis Accords will have an opportunity to send their astronauts to the moon through NASA’s lunar program. —Elizabeth Economy, Foreign Affairs, 9 Dec. 2025

The first astronauts to set foot on Mars should hunt for signs of past or present Red Planet life. —Mike Wall, Space.com, 9 Dec. 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