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

Rubio has served for more than 28 years as an Army aviator, physician and astronaut. —Chelsea Jones, CBS News, 10 June 2026

What was supposed to be a six-month mission turned into over a year, with Rubio setting the record for the longest single spaceflight by an American astronaut in the process. —Kairi Lowery, Miami Herald, 10 June 2026

The agency has no shortage of female astronauts. —Denise Chow, NBC news, 10 June 2026

Some of our favorites feature a pair of female astronauts who fall in love, women overtaken by vampirism and a man facing down the AIDS epidemic. —Caroline Killilea, PEOPLE, 10 June 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