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Definition of "cosmonaut" [cosmonaut]

  • A Russian or Soviet astronaut. (noun)

American Heritage(R) Dictionary of the English Language, Fifth Edition. Copyright (c) 2011 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.

Use "cosmonaut" in a sentence
  • "Once the cosmonaut is in then the appendix is rolled up and secured with strong elastic bands."
  • "An astronaut or cosmonaut is a person trained by a human spaceflight program to command, pilot, or serve as a crew member of a spacecraft."
  • "The Soyuz TMA-18 spacecraft will dock with the ISS on Sunday, where the crew will join Russian cosmonaut Oleg Kotov, U.S. astronaut Timothy Creamer, and Japanese astronaut Soichi Noguchi."