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

Unlike his predecessor under a Democratic president—former astronaut Charlie Bolden, who served as NASA leader under President Obama—Nelson supported the Wolf Amendment, which strictly limits cooperation between NASA and China’s space program. — Eric Berger, ArsTechnica, 23 Sep. 2026

Crew-13 will deliver four astronauts to the orbiting lab — NASA's Jessica Watkins and Luke Delaney, the Canadian Space Agency's Josh Kutryk and Sergey Teteryatnikov of Russia's federal space corporation Roscosmos. — Mike Wall, Space.com, 23 Sep. 2026

The data collected from studying the crater could help scientists develop technology that would better allow astronauts to brave and traverse the hostile environment. — Adam Kovac, Scientific American, 22 Sep. 2026

Some missiles even became launch vehicles for satellites and astronauts, carrying their military engineering into the emerging Space Age. — Atharva Gosavi, Interesting Engineering, 19 Sep. 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