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 The Crew Dragon spacecraft was launched by a SpaceX Falcon 9 rocket Sunday night from the Kennedy Space Center, kicking off a 28-hour flight to deliver three NASA astronauts and a Russian cosmonaut to the orbiting laboratory. William Harwood, CBS News, 4 Mar. 2024 Russian officials later determined that the spacecraft was not safe to transport its crew of two Russian cosmonauts and a NASA astronaut home. Christian Davenport, Washington Post, 2 Mar. 2024 The day's events include on-track tours, demonstration laps with IndyCar driver Ed Carpenter, a STEM symposium and an autograph session with NASA astronauts and IndyCar drivers. The Indianapolis Star, 1 Mar. 2024 Researchers could simulate a Mars exploration on the Moon by having astronauts conduct tasks similar to those anticipated for Mars. Discover Magazine, 26 Feb. 2024 Perhaps the most important potential of missions like Odysseus is to kindle dreams for the next generation of astronauts. Mackenzie McCarty, The Christian Science Monitor, 23 Feb. 2024 In the film, Sandler plays Jakub Prochazka, an astronaut on a solo mission to Jupiter. Eric Andersson, Peoplemag, 22 Feb. 2024 Intuitive Machines The agency's goal is to help kickstart development of new technologies and to collect data that will be needed by Artemis astronauts planning to land near the moon's south pole later this decade. William Harwood, CBS News, 22 Feb. 2024 Planned missions under the Artemis program will allow researchers to learn more about the pressures astronauts will face during the journey to Mars. Nick Kanas, The Conversation, 21 Feb. 2024

These examples are programmatically compiled from various online sources to illustrate current usage of the word 'astronaut.' Any opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback about these examples.

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

Dictionary Entries Near astronaut

Cite this Entry

“Astronaut.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/astronaut. Accessed 19 Mar. 2024.

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

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