noun · verb · 11 senses · updated from the 2026-07-25 local source snapshot
Definitions and examples are grouped by meaning. Pronunciation, history, word forms, translations, descendants, synonyms, antonyms, derived terms, and related words appear whenever the source provides them.
Sound
Pronunciation
Each Play button uses your device's default local English voice, or a natural local fallback. The selected voice name appears after playback. This is synthesized speech, not a source recording.
UK:/ˈfaɪə.wɔəl/
UK:/ˈfaɪ.əˌwɔːl/
US:/ˈfaɪ(ə)ɹˌwɔl/
US:/ˈfaɪ(ə)ɹˌwɑl/
US:Recorded audio is listed in the source snapshot.
Canada:Recorded audio is listed in the source snapshot.
CMU ARPABET:F AY1 R W AA0 L
Digits mark lexical stress: 1 primary, 2 secondary, 0 unstressed.
1
noun
Meaning 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.
Definition source: English Wiktionary via Wiktextract
Topics: architecture
No example sentence was provided for this meaning.
Meaning relationships
Synonyms: none provided
Antonyms: none provided
2
noun
Meaning 2
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.
Definition source: English Wiktionary via Wiktextract
Qualifier: computer security
No example sentence was provided for this meaning.
Meaning relationships
Synonyms: none provided
Antonyms: none provided
3
noun
Meaning 3
A hypothetical phenomenon where an observer falling into a black hole encounters high-energy quanta at or near the event horizon.
Definition source: English Wiktionary via Wiktextract
No example sentence was provided for this meaning.
Meaning relationships
Synonyms: none provided
Antonyms: none provided
4
noun
Meaning 4
An ethical wall; an organizational or legal separation between two entities that might otherwise cause conflicts of interest.
Definition source: English Wiktionary via Wiktextract
No example sentence was provided for this meaning.
Meaning relationships
Synonyms: none provided
Antonyms: none provided
5
noun
Meaning 5
An unwritten agreement among major political parties to refuse to govern or cooperate with national conservative and ultranationalist parties.
Definition source: English Wiktionary via Wiktextract
Usage: Germany, especially
Topics: government, politics
No example sentence was provided for this meaning.
Meaning relationships
Synonyms: none provided
Antonyms: none provided
6
verb
Meaning 6
To protect with a firewall.
Definition source: English Wiktionary via Wiktextract
Usage: transitive
Qualifier: computer security
No example sentence was provided for this meaning.
Meaning relationships
Synonyms: none provided
Antonyms: none provided
7
verb
Meaning 7
To block with a firewall.
Definition source: English Wiktionary via Wiktextract
Usage: transitive
Qualifier: computer security
No example sentence was provided for this meaning.
Meaning relationships
Synonyms: none provided
Antonyms: none provided
8
verb
Meaning 8
To use maximum engine power or acceleration.
Definition source: English Wiktionary via Wiktextract
Usage: intransitive, slang
Qualifier: motor vehicles or aircraft
No example sentence was provided for this meaning.
Meaning relationships
Synonyms: none provided
Antonyms: none provided
9
noun
Meaning 9
(colloquial) the application of maximum thrust
Definition source: Princeton WordNet 3.0
Examples
he moved the throttle to the firewall
Meaning relationships
Synonyms: none provided
Antonyms: none provided
Broader terms: drive, thrust, driving force
10
noun
Meaning 10
a fireproof (or fire-resistant) wall designed to prevent the spread of fire through a building or a vehicle
Definition source: Princeton WordNet 3.0
No example sentence was provided for this meaning.
Meaning relationships
Synonyms: none provided
Antonyms: none provided
Broader terms: wall
11
noun
Meaning 11
(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
Definition source: Princeton WordNet 3.0
No example sentence was provided for this meaning.
Meaning relationships
Synonyms: none provided
Antonyms: none provided
Broader terms: security system
History
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.
Across languages
Translations
117 source translations are retained for this English entry.