noun C1 Advanced Uncommon

firewall

FEYE-uh-waw-uhl

Firewall (noun) means a fireproof barrier built to stop fire from spreading between parts of a building or vehicle. Example: “The garage was separated from the house by a firewall.”

noun

A fireproof barrier built to stop fire from spreading between parts of a building or vehicle.

"The garage was separated from the house by a firewall."

Software that monitors and controls network traffic to block unauthorized access.

"The company firewall blocked the suspicious connection automatically."

"Make sure your firewall is enabled before connecting to public Wi-Fi."

A strict separation kept between two parts of an organization to avoid conflicts of interest.

"There's meant to be a firewall between the newsroom and the advertising department."

How to use firewall

Learner’s notes

In plain EnglishA barrier that blocks something harmful from spreading — physical fire, network threats, or conflicts of interest.

Common pairings

set up a firewall behind a firewall ethical firewall

Word forms

firewalled past tense, firewalls plural, firewalls singular

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Can you complete this real example?

The garage was separated from the house by a _____.

Etymology

From fire and wall. The computing sense builds on the image of a physical barrier that blocks the spread of something dangerous.

Rhymes for firewall

stonewall

See all rhymes for firewall →

Frequently asked questions

What does “firewall” mean?

The word “firewall” means a fireproof barrier built to stop fire from spreading between parts of a building or vehicle. In plain terms, a barrier that blocks something harmful from spreading — physical fire, network threats, or conflicts of interest.

How do you pronounce “firewall”?

“Firewall” is pronounced FEYE-uh-waw-uhl (/ˈfaɪ(ə)ɹˌwɔl/ in IPA).

How do you use “firewall” in a sentence?

Here is “firewall” used in a sentence: “The garage was separated from the house by a firewall.”

What part of speech is “firewall”?

“Firewall” is a noun.

Is “firewall” a common word?

“Firewall” is an uncommon word in modern English, usually learned at around the C1 level.

How many meanings does “firewall” have?

“Firewall” has 3 distinct senses listed in this dictionary. The most common is: a fireproof barrier built to stop fire from spreading between parts of a building or vehicle.