The definition of an astronaut is a person who either travels into space or who is trained to travel into space.(noun)
An example of an astronaut is Neil Armstrong, the man who walked on the moon.
See astronaut in Webster's New World College Dictionary
Origin: < Fr astronaute: see astro- & aeronaut
See astronaut in American Heritage Dictionary 4
Origin: + Greek nautēs, sailor (from naus, ship; see nāu- in Indo-European roots).
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