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

During April’s Artemis II mission, four astronauts flew around the moon, traveling deeper into space than the Apollo moon crews did during the late 1960s and early 1970s. —Marcia Dunn, Fortune, 27 May 2026

If all goes well with Artemis 3 and other developments, Artemis 4 will put astronauts down near the lunar south pole in late 2028. —Mike Wall, Space.com, 27 May 2026

An astronaut suddenly couldn’t speak in space A health scare prompted the first-ever early return from the International Space Station for a medical reason. —Alexandra Banner, CNN Money, 27 May 2026

This remote lunar region is the intended site of future Artemis astronaut landings and, of course, the much ballyhooed moon base. —Dan Vergano, Scientific American, 27 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