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.

Definitions of astronaut

n a person trained to travel in a spacecraft

“the Russians called their astronauts cosmonauts”
cosmonaut, spaceman
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Neil Armstrong
United States astronaut; the first man to set foot on the Moon (July 20, 1969) (1930-)
Yuri Alekseyevich Gagarin
Soviet cosmonaut who in 1961 was the first person to travel in space (1934-1968)
John Herschel Glenn Jr.
made the first orbital rocket-powered flight by a United States astronaut in 1962; later in United States Senate (1921-)
Alan Bartlett Shepard Jr.
astronaut who made the first United States' suborbital rocket-powered flight in 1961 (1923-1998)
Valentina Vladmirovna Tereshkova
Soviet cosmonaut who was the first woman in space (born in 1937)
an astronaut who is active outside a spacecraft in outer space
Type of:
traveler, traveller
a person who changes location

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