a person trained to travel in a spacecraft同义词：spaceman, cosmonaut
例句
The astronaut accepted danger was part of the job.太空人承认他们的工作中包含著危险。
The astronaut can send out a robot which will work on the unknown planet, collecting rocks and minerals, putting up a permanent observation station or traveling far and wide.宇航员可以派出机器人在这颗陌生的行星上工作，收集岩石和矿物; 建立永久性观察站，或向四面八方走动。
My son's dream is to be an astronaut.我儿子的理想是当宇航员。
A rocket manned by trained astronauts will launch soon.载有受过训练的宇航员的火箭马上就要发射了。
详细解释
as.tro.naut n.（名词）A person trained to pilot, navigate, or otherwise participate in the flight of a spacecraft.宇航员：在宇宙飞船的飞行中训练来导航，驾驶航天飞机，或参与其它活动的人员 来源：astro-astro-Greek nautôs [sailor] from naus [ship] * see n3u- 希腊语 nautôs [水手] 源自 naus [船] *参见 n3u-