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

This research aims to explain how Mars lost its atmosphere, transitioning from a wet to a dry environment, and to help protect future astronauts from radiation. —Mrigakshi Dixit, Interesting Engineering, 14 Nov. 2025

The new crew on board the Shenzhou-21 – who are now without a spaceship to return in – include China’s youngest astronaut to be sent to space, 32-year-old Wu Fei. —Jessie Yeung, CNN Money, 14 Nov. 2025

In addition to stranding the three Chinese astronauts – called taikonauts – who were set to return to Earth, this incident highlights the increasing risks posed to China and the broader international community by the growing amount of space debris. —R. Lincoln Hines, The Conversation, 13 Nov. 2025

Formed in 2000 by Jeff Bezos, Blue Origin has a NASA contract for the third moon landing by astronauts under the Artemis program. —Emma Bussey, FOXNews.com, 13 Nov. 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