conscience
/ˈkɔnʃəns; `kɑnʃəns/ n[C, U]
1 person's awareness of right and wrong with regard to his own thoughts and actions 良心; 是非感
have a clear/guilty conscience, ie feel one has done right/wrong 问心无[有]愧
After she had committed the crime, her conscience was troubled, ie she felt very guilty. 她犯罪後, 良心上感到很不安.
She cheerfully cheats and lies; she's got no conscience at all. 她以撒谎和骗人为乐, 完全没有良心.
I must go. It's a matter of conscience, ie I think it would be morally wrong not to go. 我必须去, 这是有关良心的事（不去对不起自己的良心）.
prisoners of conscience, ie people imprisoned because they believe it is wrong to support a political system, etc 政治犯（认为拥护某政治制度等是错误的因而被关押者）.
2 (idm 习语) ease sb's conscience/mind => ease2. have sth on one's conscience feel troubled about sth one has done or failed to do 因做了某事或未能做某事而内疚
He has several murders on his conscience. 他因为谋害了几个人而受到良心的谴责. in all conscience by any reasonable standard 当然; 的确; 凭良心
You cannot in all conscience regard that as fair pay. 你在良心上总不能认为那样的报酬算是合理的吧. on one's `conscience making one feel one has done wrong, or left sth undone 使人觉得自己做错了事或该做某事而未做
It's still on my conscience that I didn't warn her in time. 我未能及时提醒她, 这事至今使我耿耿於怀. search one's heart/conscience => search.