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firewall

American  
[fahyuhr-wawl] / ˈfaɪərˌwɔl /
Or fire wall

noun

  1. a partition made of fireproof material to prevent the spread of a fire from one part of a building or ship to another or to isolate an engine compartment, as on a plane, automobile, etc.

  2. a person, thing, or event that acts as a barrier or protection against something undesirable.

    The new employee handbook should create a firewall against unethical business conduct.

  3. Digital Technology. an integrated collection of security measures designed to prevent unauthorized electronic access to a networked computer system.


firewall British  

noun

  1. a fireproof wall or partition used to impede the progress of a fire, as from one room or compartment to another

  2. computing a computer system that isolates another computer from the internet in order to prevent unauthorized access

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

firewall Scientific  
/ fîrwôl′ /
  1. A software program or hardware device that restricts communication between a private network or computer system and outside networks.


firewall Cultural  
  1. A means of separating a computer network from outside networks for security purposes. A server outside an organization's own network may be used to funnel all incoming and outgoing traffic to assist in keeping out viruses, as well as to prevent unauthorized outsiders from gaining access to a network.


Etymology

Origin of firewall

An Americanism dating back to 1750–60

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

The talk is of ensuring that there is a firewall between the King and the legal and police inquiries so that they can proceed cleanly.

From BBC

Following the latest revelations, historian David Olusoga told BBC Newsnight there is now "a desperate desire within government and within the palace to draw a firewall… between this crisis and the wider monarchy".

From BBC

The existing players in cybersecurity provide businesses with complex firewalls: software that identifies customers’ internal users of data, and tools that allow or disallow access to information for parties external to the customer.

From Barron's

Meanwhile, Morgan Stanley analyst Meta Marshall wrote of “continued momentum and firewall share gains” that may have driven Palo Alto Networks’ revenue above the 17% to 18% growth rate that the company had projected.

From MarketWatch

Within days memes became the currency of these American "TikTok refugees" as two worlds that rarely interact because of China's internet firewall were brought closer.

From BBC