astronaut
Americannoun
noun
Other Word Forms
Noun Inflected Forms
Etymology
Origin of astronaut
1925–30; astro- + (aero)naut, probably via French astronaute; see astronautical
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Explanation
An astronaut is someone who travels in space. While the term was once reserved for military-trained professionals, recent accessibility of space travel has seen the term astronaut now used to refer to anyone traveling in a spacecraft, including civilians. The word astronaut includes the root naut, from nautes, the Greek word for "sailor." This suffix can be used to create many travel-specific words. For example, the Argonauts were mythical Greek sailors on the ship named the Argo. Astronaut gets the astro from the Greek word astron, meaning "star," making an astronaut a “star sailor.” Russian space explorers took the title cosmonauts, with the cosmo part coming from the Greek for "universe," kosmos, so both have the same meaning.
Vocabulary lists containing astronaut
Occupations
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Elements of the Universe: Aster, Astro ("Star")
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astro, aster
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Example Sentences
Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.
Astronaut Christina Koch said the so-called Universal Waste Management System was giving off "a burning heater smell."
From Barron's • Apr. 9, 2026
After her first flight, she served as deputy chief of NASA's Astronaut Office.
From Science Daily • Jan. 22, 2026
Astronaut Jim Lovell, who guided the Apollo 13 mission safely back to Earth in 1970, has died aged 97.
From BBC • Aug. 8, 2025
NS-31 Astronaut Lauren Sánchez celebrates a successful mission to space.
From Salon • Apr. 17, 2025
Astronaut is Greek for “star voyager” or “star sailor.”
From "Women in Space" by Karen Bush Gibson
Definitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023
Idioms from The American Heritage® Idioms Dictionary copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.
