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

In that time, astronauts must endure radiation, bone loss, muscle wasting, isolation, and limited food supplies. —Kaif Shaikh, Interesting Engineering, 16 Oct. 2025

And before Starship can launch with any astronauts on board, SpaceX officials have said, hundreds of test missions are necessary. —Denise Chow, NBC news, 16 Oct. 2025

The basin is located in a region where NASA astronauts are due to land as early as 2027, presenting an opportunity to collect some samples to return to Earh, researchers claim. —Eric Lagatta, USA Today, 16 Oct. 2025

To make budgetary room for this bold endeavor, the duo advocated cutting the behind-schedule and over-budget Space Launch System (SLS), the super-heavy lift rocket intended to take astronauts back to the Moon with the Artemis program. —Big Think, 15 Oct. 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