unfair treatment of somebody who trusts you synonym treachery背叛;背信棄義 In Act 2 he learns of Giovanni’s perfidy and swears revenge. 在第二幕中,他知道了喬瓦尼的背信棄義,發誓要報仇。
Word Originlate 16th cent.: via French from Latin perfidia, from perfidus ‘treacherous’, based on per- ‘to ill effect’ + fides ‘faith’.