Wiktionary
alt. (context legal business English) A contract that enjoins a party not to disclose certain information. n. (context legal business English) A contract that enjoins a party not to disclose certain information.
Wikipedia
A non-disclosure agreement (NDA), also known as a confidentiality agreement (CA), confidential disclosure agreement (CDA), proprietary information agreement (PIA), or secrecy agreement (SA), is a legal contract between at least two parties that outlines confidential material, knowledge, or information that the parties wish to share with one another for certain purposes, but wish to restrict access to or by third parties. It is a contract through which the parties agree not to disclose information covered by the agreement. An NDA creates a confidential relationship between the parties to protect any type of confidential and proprietary information or trade secrets. As such, an NDA protects non-public business information.
NDAs are commonly signed when two companies, individuals, or other entities (such as partnerships, societies, etc.) are considering doing business and need to understand the processes used in each other's business for the purpose of evaluating the potential business relationship. NDAs can be "mutual", meaning both parties are restricted in their use of the materials provided, or they can restrict the use of material by a single party.
It is also possible for an employee to sign an NDA or NDA-like agreement with an employer. In fact, some employment agreements will include a clause restricting employees' use and dissemination of company-owned confidential information.
Usage examples of "non-disclosure agreement".
I am certain you all remember the non-disclosure agreement you signed when you took this job?
You'll need a security clearance, and you'll need to sign a very strict non-disclosure agreement.
Under the terms of the White House Non-Disclosure Agreement, the Chief of Staff, through the director of White House communications, tells you to whom you can and cannot give statements.
He meant, did I have a non-disclosure agreement that would prevent me from discussing what I had just heard.