inexcusably 

英汉解释

adv. 无法原谅地；无法辩解地

同义词

r. unforgivably，unjustifiably，unpardonably

反义词

r.   excusably，forgivably，justifiably，with reason

参考例句

1. he was inexcusably cruel to his wife.
他对妻子那么残酷是无法原谅。
2. Her heart misgave her that she had acted inexcusably.
她的心情使她忧虑她表现地无法原谅。
3. Initially deemed a failure, the new design has since won over those who regard consistency as inexcusably boring.
这项新设计最初曾被认为是一项失败之举，最终却赢得了那些曾认为这是无聊之举的公众的一致认可。

英英解释

adv.
  1. in an unpardonable manner or to an unpardonable degree
  2. without any excuse

网络释义

inexcusably
无法原谅地; 无法辨解地; 不可原谅;