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

The agency is charged with landing astronauts on the Moon before China, perhaps as soon as 2028, and following that achievement with the build-out of a permanent base near the south pole. —Stephen Clark, ArsTechnica, 6 May 2026

Before an astronaut leaves Earth to usher in a new era of spaceflight, his son asks him to confront the unresolved space between them—revisiting a past shaped by distance in the hope of a more connected future. —Matthew Carey, Deadline, 6 May 2026

What astronauts are on the International Space Station? —Eric Lagatta, USA Today, 6 May 2026

Voice recordings that the Artemis II astronauts made during their flyby of the moon will also eventually be available there, along with a user’s guide compiled by the mission’s science team to help researchers make the most of the information. —Meghan Bartels, Scientific American, 4 May 2026

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