confidential

adj

1. Kept, or meant to be kept, secret within a certain circle of persons; not intended to be known publicly.

   “The newspaper claims a leaked confidential report by the government admits to problems with corrupt MPs.”

   “[…]I have a communication of a very private—indeed, I will say, of a sacredly confidential nature, which I desire to make to you.”

   “It would tell against your reputation, losing a confidential document, wouldn’t it? Why didn’t you keep it confidential if it was confidential?”

   ““One of the things that I think parents would tell you, and that students and victims and patients would tell you, is that we have a legal responsibility, but I think more importantly a moral responsibility, to hold their information confidential and private,” Blanton said.”

2. (dated)Inclined to share confidences; (of things) making people inclined to share confidences; involving the sharing of confidences.

   “Sitting in front of the fire, they became quite confidential, and began to gossip.”

   “Long, long would it be ere Miss Crawford′s name passed his lips again, or she could hope for a renewal of such confidential intercourse as had been.”

   “I was only alive to the condensed confidential comfortableness of sharing a pipe and a blanket with a real friend.”

   “She and Bertha had never been on confidential terms, but at such a crisis the barriers of reserve must surely fall:[…]”

   “Miss Raste was encouraged to be entirely confidential, to withhold nothing even about herself, by the confidence-inspiring and kindly aspect of Elsie’s face.”

3. (dated)Having someone's confidence or trust; having a position requiring trust; worthy of being trusted with confidences.

   “a confidential agent”

   “a confidential servant”

   “a confidential whisper”

   “Now, they want me to send up a confidential person with some writings.”

   “This paper will serve instead of a confidential friend into whose ear I might pour forth the overflowings of my heart.”