astronaut

noun

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
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Tensions rise when a mysterious astronaut, played by Aaron Paul, shows up. William Earl, Variety, 21 Mar. 2025 The agency had astronauts in orbit, rockets to launch, and astronomical data to decipher. David W. Brown, The New Yorker, 21 Mar. 2025 Starliner saga: See photos of astronauts landing, exiting SpaceX Dragon in Florida When will Venus pass between Earth, sun? Between Saturday night and Sunday morning, Venus will pass between the Earth and sun during its inferior conjunction. Eric Lagatta, USA TODAY, 21 Mar. 2025 The amnesiac astronaut steps outside briefly before realizing that the oxygen levels are unsuited to her human body. Lovia Gyarkye, The Hollywood Reporter, 20 Mar. 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 29 Mar. 2025.

Kids Definition

astronaut

noun
: 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

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