• adjective:   entrusted with private information and the confidence of another

  Example: "A confidential secretary"

• adjective:   the level of official classification for documents next above restricted and below secret; available only to persons authorized to see documents so classified
• adjective:   denoting confidence or intimacy

  Example: "A confidential approach"

• adjective:   (of information) given in confidence or in secret

  Example: "This arrangement must be kept confidential"

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