astronaut
Americannoun
noun
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.
What happens on a summer night when an astronaut casts his eyes on the moon.
From The Wall Street Journal • Apr. 12, 2026
“I would suggest to you that when you look up here, you’re not looking at us,” said Canadian Space Agency astronaut and Artemis II mission specialist astronaut Jeremy Hansen, back in Houston Saturday.
From Los Angeles Times • Apr. 12, 2026
Flanked on stage by mission commander Reid Wiseman, Victor Glover and Jeremy Hansen, astronaut Christina Koch called for people on Earth to embrace their shared humanity.
From Barron's • Apr. 11, 2026
Most astronauts, including the first British astronaut Helen Sharman, have described how they don't want to come home because the work in space is so exciting.
From BBC • Apr. 10, 2026
The mission would study the effects of space on a geriatric astronaut.
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.
