vertraulich
confidential
Not intended for the public; to be kept secret.
Diese Dokumente sind streng vertraulich und dürfen den Raum nicht verlassen.
These documents are strictly confidential and must not leave the room.

confidential
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confidential
Not intended for the public; to be kept secret.
Diese Dokumente sind streng vertraulich und dürfen den Raum nicht verlassen.
These documents are strictly confidential and must not leave the room.

The adjective 'vertraulich' (confidential) is derived from the noun 'das Vertrauen' (trust). It describes something that is based on trust or requires trust.
Danke für deine Offenheit, ich schätze unser vertrauliches Verhältnis.
Thank you for your openness; I appreciate our confidential relationship.
If 'vertraulich' (confidential) refers to information or documents, it means 'secret'. If it refers to a conversation or atmosphere, it means 'personal and shaped by trust'.
Bitte behandeln Sie diese Kundenliste streng vertraulich.
Please treat this customer list as strictly confidential.
In the meaning 'secret', the word is often combined with nouns like 'Dokumente' (documents), 'Informationen' (information), 'Daten' (data), or 'Angelegenheit' (matter). A very common phrase is 'etwas vertraulich behandeln' (to treat something as confidential).
Alle Mitarbeiter müssen eine Vereinbarung unterschreiben, um Firmendaten vertraulich zu behandeln.
All employees must sign an agreement to treat company data as confidential.
In the meaning 'shaped by trust', it often describes the type of communication, e.g. 'ein vertrauliches Gespräch' (a confidential conversation), 'ein vertraulicher Brief' (a confidential letter), or 'ein vertraulicher Ton' (a confidential tone).
In vertraulicher Atmosphäre erzählte sie von ihren Plänen.
In a confidential atmosphere, she talked about her plans.
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'unter vier Augen' (in private, between two people) and 'vertraulich' both fit situations where not everyone is supposed to listen in or know everything. 'unter vier Augen' means a conversation between exactly two people. 'vertraulich' describes the content or the atmosphere: the information should remain secret, or the conversation is shaped by trust. A confidential conversation can take place 'unter vier Augen', but it does not have to. It can also be confidential in a small group.

Das Team behandelt die Informationen vertraulich, weil es um persönliche Daten geht.
The team handles the information confidentially because it involves personal data.
Die Mitarbeiterin spricht morgen unter vier Augen mit ihrer Chefin.
The employee will speak with her boss in private tomorrow.