impotent
adjective uk/ˈɪm.pə.tənt/ us/ˈɪm.pə.t̬ənt/
(LACKING POWER)
无力量的；无能力的
not having the power or ability to change or improve a situation
You feel so impotent when your child is ill and you cannot help them. 当孩子生病却什么忙也帮不上时，你会觉得自己是如此无能为力。
(SEXUAL PROBLEM)
（男子）阳痿的
If a man is impotent, he cannot have sex because his penis cannot become hard or stay hard.
（男性）不育的
If a man is impotent, he is unable to have children.