confidential
adj
1 to be kept secret; not to be made known to others 恪守秘密的; 机密的
confidential information, files, letters 机密情报、 文件、 信件.
2 [attrib 作定语]
trusted with secrets 获得信任参与机密的
a confidential secretary 机要秘书.
3 trusting 表示信任的: speaking in a confidential tone 用表示信任的口吻说话.