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

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Examples of astronaut in a Sentence

Recent Examples on the Web

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

In November 2025, three Chinese astronauts aboard the Tiangong space station were forced to delay their return to Earth because their capsule had been struck by a piece of space debris. —Mojtaba Akhavan-Tafti, The Conversation, 3 Dec. 2025

December’s full moon also occurs ahead of the launch of Artemis II, anticipated between February and April 2026, which will send a crew of four astronauts on a 10-day journey around the moon. —Gina Park, CNN Money, 3 Dec. 2025

The good news: three astronauts aboard a Soyuz MS-28 spacecraft successfully reached the orbital outpost after a Thanksgiving Day launch. —Eric Lagatta, USA Today, 2 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