Of a person: intimate or familiar (with someone; cf. private, adj.1 7b); trusted; belonging to one's close circle of friends or companions. Obsolete.

That is entrusted with a person's private or secret affairs; that is a confidant; intimate with.

Of a person: intimate or confidential (with a person); sexually intimate. Obsolete.

Betokening private intimacy, or the confiding of private secrets.