A person trained to pilot, navigate, or otherwise participate as a crew member of a spacecraft.(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 "astronaut" in a sentence
"The male TFNGs were learning there was an even more powerful pheromone than jet-jockey wings and the SEAL insignia: the title astronaut."
"The lower-case-a "astronaut" is someone who has flown in space, either aboard a US spacecraft or who is an American."
"Each astronaut is allowed a "bonus food allotment" to bring some of the comforts of home to outer space."