astronaut

noun as·tro·naut \ ˈas-trə-ˌnȯt , -ˌnät \
Updated on: 11 Nov 2017

Definition of astronaut

: a person who travels beyond the earth's atmosphere; also : a trainee for spaceflight

Recent Examples of astronaut from the Web

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'astronaut.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

Origin and Etymology of astronaut

astr- + -naut (as in aeronaut)

Other Aeronautics/Aerospace Terms


ASTRONAUT Defined for English Language Learners

astronaut

noun

Definition of astronaut for English Language Learners

  • : a person who travels in a spacecraft into outer space


ASTRONAUT Defined for Kids

astronaut

noun as·tro·naut \ ˈa-strə-ˌnȯt \

Definition of astronaut for Students

: a person who travels beyond the earth's atmosphere : a traveler in a spacecraft


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