confidant
/ˌkɒnfɪˈdænt/noun
(fem. 阴性 confidante. 读音同)
- a person with whom one shares a secret or private matter, trusting them not to repeat it to others（可向之透露秘密或个人私事的）密友, 知己。
词源
mid 17th cent.: alteration of CONFIDENT （as a noun in the same sense in the early 17th cent.）， probably to represent the pronunciation of French confidente 'having full trust'.