weightless
adjective uk/ˈweɪt.ləs/ us/ˈweɪt.ləs/
无重量的；失重的；似无重量的
having or appearing to have no weight
There is a lot of interest in carrying out experiments in the weightless conditions which are experienced aboard space stations. 在空间站那种失重状态下做实验非常有趣。
Compare: weighty