confidential

adj

1.
entrusted with private information and the confidence of another
Derived from:
confidence
2.
(of information) given in confidence or in secret
secret
Derived from:
confidence confidentiality
3.
denoting confidence or intimacy
Derived from:
confidence
4.
the level of official classification for documents next above restricted and below secret; available only to persons authorized to see documents so classified
Derived from:
confidentiality