What does "firewall" mean?
A fireproof barrier used to prevent the spread of fire between or through buildings, structures, electrical substation transformers, or within an aircraft or vehicle.
Firewall
/ˈfaɪ(ə)ɹˌwɔl/ noun, verb, slang
noun, verb, slang ·Moderate ·High school level
Meaning at a glance
- Primary sense: A fireproof barrier used to prevent the spread of fire between or through buildings, structures, electrical substation transformers, or within an aircraft or vehicle.
- Grammar: firewall is listed as noun, verb, slang.
- Nearest alternatives: data boundary, data separation, fire barrier, fire containment.
- Useful contrasts: data integration, flammable barrier, gateway.
- Usage evidence: A firewall will guarantee Internet security.
How to use "firewall"
- Start with the primary definition, then check the part of speech before placing the word in a sentence.
- Compare nearby synonyms to make sure "firewall" carries the exact meaning, tone, and strength you need.
- Use the example sentence as a context check. If your sentence uses the word differently, confirm that the grammar still fits.
Meaning check
- Does the word fit the sentence's grammar?
- Does it match the intended tone rather than only the dictionary definition?
- Would a simpler synonym be clearer for the reader?
- Is there enough surrounding context to prevent ambiguity?
Source and review context
This entry combines structured lexical data with WordToolSet review checks. Definitions, examples, synonyms, and usage notes may come from different source tables, so the page is designed to show evidence from more than one angle before you rely on "firewall" in a final draft.
If a word has several senses, prefer the sense that matches your sentence's grammar and surrounding context. A correct definition can still be the wrong choice when the sentence needs a different register, emphasis, or level of specificity.
Before you rely on this definition
Read the first definition as a starting point, then check the example, synonyms, and part of speech before treating "firewall" as the right word for your sentence.
If your draft is formal, technical, persuasive, or sensitive, compare "firewall" with a nearby alternative so the final choice matches both meaning and reader expectation.
Compare nearby meanings
- Use synonyms when you need a softer, stronger, simpler, or more specific word.
- Use antonyms to check the boundary of the meaning and avoid accidental contrast.
- Use the example sentence to confirm the word behaves naturally in context.
- Keep the original wording when a replacement adds complexity without improving precision.
Definition decision workflow
1. Identify the role
Check whether "firewall" is acting as noun, verb, slang in your sentence. A definition is only useful when the grammar matches the way the word is being used.
2. Test the nearest option
Compare it with "data boundary" and other nearby choices to see whether the sentence needs a softer, stronger, or more familiar word.
3. Confirm with context
Use the example sentence below as an evidence check, then read your own sentence out loud to catch tone or rhythm problems.
Review note: Definition pages are checked for source coverage, sentence evidence, synonym support, and editorial insight before they are treated as approval-ready pages. If the evidence is too thin, the page remains available to users but is kept out of the approval-facing indexed inventory.
Final meaning check
Before publishing a sentence with "firewall", ask whether the word helps the reader understand the idea faster. A precise word should reduce confusion, not simply make the sentence look more polished.
When the definition, synonym evidence, and example context point in the same direction, the word is usually a safer choice. When they conflict, revise the sentence or choose a clearer alternative.
Definitions
Noun
- 1 A fireproof barrier used to prevent the spread of fire between or through buildings, structures, electrical substation transformers, or within an aircraft or vehicle.
- 2 (colloquial) the application of maximum thrust wordnet
- 3 The software that monitors traffic in and out of a private network or a personal computer and allows or blocks such traffic depending on its perceived threat.
- 4 a fireproof (or fire-resistant) wall designed to prevent the spread of fire through a building or a vehicle wordnet
- 5 A hypothetical phenomenon where an observer falling into a black hole encounters high-energy quanta at or near the event horizon.
Show 3 more definitions
- 6 (computing) a security system consisting of a combination of hardware and software that limits the exposure of a computer or computer network to attack from crackers; commonly used on local area networks that are connected to the internet wordnet
- 7 An ethical wall; an organizational or legal separation between two entities that might otherwise cause conflicts of interest.
"The book explains this in Adam Hochberg's (@adamhochberg) chapter discussing the Wisconsin Center for Investigative Journalism's concerns related to non-profit news organizations: donor transparency, editorial independence, the firewall between journalism and fundraising, and conflicts of interest."
- 8 An unwritten agreement among major political parties to refuse to govern or cooperate with national conservative and ultranationalist parties. Germany, especially
""Honest government must be preceded by honest negotiations," Mr Kickl said when Austria's president tasked him with beginning coalition talks after the centrist firewall failed."
Verb
- 1 To protect with a firewall. transitive
- 2 To block with a firewall. transitive
- 3 To use maximum engine power or acceleration. intransitive, slang
Synonyms
All synonyms data boundarydata separationfire barrierfire containmentfire wallinformation boundary
Antonyms
Example
"A firewall will guarantee Internet security."
Common questions
What is a synonym for "firewall"?
Common synonyms include: data boundary, data separation, fire barrier, fire containment, fire wall, information boundary.
How do you use "firewall" in a sentence?
A firewall will guarantee Internet security.
How do you pronounce "firewall"?
Pronounced /ˈfaɪ(ə)ɹˌwɔl/.
Etymology
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.