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firewall

or fire wall

[fahyuh r-wawl]
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.
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Origin of firewall

An Americanism dating back to 1750–60
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018

Examples from the Web for firewall

Contemporary Examples

Historical Examples

  • Apparently the foul-up is on the other side of the firewall.

    The Bramble Bush

    Gordon Randall Garrett

  • The temperature behind the firewall had risen to two-forty Centigrade.

    The Bramble Bush

    Gordon Randall Garrett

  • "They're probably both stuck at the firewall," Willows said.

    The Bramble Bush

    Gordon Randall Garrett

  • He went into the antechamber of the reactor and glared at the door in the firewall.

    The Bramble Bush

    Gordon Randall Garrett

  • You try to get an experimental service running and no one will reconfigure the firewall.

    Makers

    Cory Doctorow


British Dictionary definitions for firewall

firewall

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
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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

Word Origin and History for firewall

n.

1851 as a physical wall meant to prevent the spread of fire in a structure, from fire (n.) + wall (n.). Computer sense is by 1990.

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Online Etymology Dictionary, © 2010 Douglas Harper

firewall in Science

firewall

[fîrwôl′]
  1. A software program or hardware device that restricts communication between a private network or computer system and outside networks.
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The American Heritage® Science Dictionary Copyright © 2011. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.

firewall in Culture

firewall

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.

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The New Dictionary of Cultural Literacy, Third Edition Copyright © 2005 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.