English Reference
noun · verb

firewall

n. · v.
US /ˈfaɪɹwɑɫ/ UK /fˈaɪəwɔːl/ fire·wall

  1. 01 B2 Upper Intermediate Computing

    n.software or hardware that protects a computer network by blocking dangerous traffic from the internet.

    n.a security system consisting of software or hardware that monitors and controls incoming and outgoing network traffic based on predetermined security rules.

    Simple

    You should update your firewall to protect your computer from the latest viruses.

    In context

    The corporate firewall blocked the suspicious connection attempt before the malware could infiltrate the internal server.

    Usage

    Often used with the verbs 'set up', 'configure', or 'bypass'.

    security barrierfilter
  2. 02 C1 Advanced Technical

    n.a wall made of special materials that stops a fire from moving from one part of a building to another.

    n.a fireproof barrier designed to prevent the spread of fire between or through buildings, structures, or vehicles.

    Simple

    The warehouse was saved because the firewall stopped the flames from reaching the office.

    In context

    Building regulations require a reinforced firewall between the garage and the living quarters to ensure resident safety in the event of a vehicle fire.

    fire partitionbarrier
  3. 03 C1 Advanced Formal Law

    n.a rule or agreement that keeps two groups apart to prevent a conflict of interest or bad influence.

    n.a metaphorical barrier or ethical wall established to prevent communication or cooperation between entities, often to avoid conflicts of interest.

    Simple

    The company created a firewall between the two departments to keep client information private.

    In context

    The mainstream parties maintained a political firewall, refusing to enter into any coalition agreements with the extremist faction.

    ethical wallbuffer
  4. 04 C1 Advanced Technical Computing

    v.to protect a system using a firewall or to block a specific connection.

    v.to protect a network or device with a firewall; to isolate a segment of a system for security purposes.

    Simple

    The IT department decided to firewall the sensitive database from the rest of the office network.

    In context

    By firewalling the guest Wi-Fi, the administrator ensured that visitors could not access the company's internal files.

  5. 05 C2 Proficiency SlangInformal

    v.to use the maximum power of an engine or to drive as fast as possible.

    v.to operate an engine at maximum throttle or to accelerate a vehicle to its limit.

    Simple

    He decided to firewall the car on the open highway to see how fast it could go.

    In context

    The pilot had to firewall the engines to clear the ridge during the emergency ascent.

    Teacher's tip

    This sense is highly informal and specific to automotive or aviation contexts; most learners will only encounter the computing sense.

    deceleratebrake

From fire + wall. Compare West Frisian brânmuorre, Dutch brandmuur, German Brandmauer, Feuermauer, Swedish brandvägg, brandmur, Icelandic eldvegg. The verb sense for using maximum power or acceleration comes from the engine's firewall being the limit of forward movement of the throttle controls on many simpler vehicles; thus, to get the maximum engine output, one would push the throttle levers or pedal all the way to the firewall. The politics sense is a calque of German Brandmauer.

Etymology adapted from Wiktionary, available under CC BY-SA 4.0.

This entry
Level B2 · Upper Intermediate
Frequency Frequent
Updated