astronaut

noun

as·​tro·​naut ˈa-strə-ˌnȯt How to pronounce astronaut (audio)
-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

Examples of astronaut in a Sentence

Recent Examples on the Web
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
Soon, Martin is fully submerged in Janine’s imaginative activities, pretending to be an astronaut in space and chuckling when a foam rocket hits Gregory in the face. Ile-Ife Okantah, Vulture, 17 Apr. 2025 The mission, which was funded by Jeff Bezos’ private space company Blue Origin, featured the first all-female crew to go to space since Russian astronaut Valentina Tereshkova orbited the Earth alone in 1963. Vrinda Jagota, Pitchfork, 15 Apr. 2025 According to Morales, a focus of the research is seeing if a plant can produce enough to feed a group of four, providing long-term nutrients for astronauts who want to visit Mars or return to the moon. Uma Raja, Sun Sentinel, 14 Apr. 2025 While many of the other female astronauts had big grins on their faces, King looked a little uncertain. Josh Hammer, MSNBC Newsweek, 14 Apr. 2025 See All Example Sentences for astronaut

Word History

Etymology

astro- + -naut (in aeronaut)

Note: See note at astronautics.

First Known Use

1928, in the meaning defined above

Time Traveler
The first known use of astronaut was in 1928

Browse Nearby Words

Cite this Entry

“Astronaut.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/astronaut. Accessed 27 Apr. 2025.

Kids Definition

astronaut

noun
as·​tro·​naut ˈas-trə-ˌnȯt How to pronounce astronaut (audio)
-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

More from Merriam-Webster on astronaut

Last Updated: - Updated example sentences
Love words? Need even more definitions?

Subscribe to America's largest dictionary and get thousands more definitions and advanced search—ad free!