In American English, 'r' can change the vowel before it. For many speakers, beard does not have quite the same vowel as either bid or bead, father does not have quite the same vowel as farther, and cord does not have quite the same vowel as cawed.

Depending on the speaker's dialect, the vowel of cord and war can be either /o/, /ɔ/, or somewhere in between. Further, it can have r-coloration, which means that the vowel is modified so that it sounds like the vowel and the consonant /r/ are being pronounced simultaneously; see this Wikipedia article on r-colored vowels. Thus, while some Americans have exactly the same vowel in war and talk, most don't.

Answer from Peter Shor on Stack Exchange
war
/wôr/
noun
  1. A state of open, armed, often prolonged conflict carried on between nations, states, or parties.
  2. The period of such conflict.
  3. The techniques and procedures of war; military science.
from The American Heritage® Dictionary of the English Language, 5th Edition. More at Wordnik
🌐
Cambridge Dictionary
dictionary.cambridge.org › us › pronunciation › english › war
How to pronounce WAR in English
How to pronounce WAR. How to say WAR. Listen to the audio pronunciation in the Cambridge English Dictionary. Learn more.
🌐
Encyclopedia Britannica
britannica.com › dictionary › eb › audio
How to Pronounce war - (Audio) | Britannica Dictionary
Meta description: Hear the pronunciation of war in American English, spoken by real native speakers. From North America's leading language experts, Britannica Dictionary
🌐
Wiktionary
en.wiktionary.org › wiki › war
war - Wiktionary, the free dictionary
Related to Old High German werra (“confusion, strife, quarrel”) and German verwirren (“to confuse”), but not to Wehr (“defense”). Also related to Old Saxon werran (“to confuse, perplex”), Dutch war (“confusion, disarray”), West Frisian war (“confusion”), Old English wyrsa, wiersa (“worse”), Old Norse verri (“worse, orig. confounded, mixed up”), Italian guerra (“war”). There may be a connection with worse and wurst. [edit] (Received Pronunciation) IPA(key): /wɔː/ (General American) IPA(key): /wɔɹ/ (Indic) IPA(key): /wɔ(r)/, (father-bother merger) /wɑ(r)
Discussions

pronunciation vs spelling - Why isn't the vowel in the words "warm" and "war" (in American English) pronounced like the one in the word "talk" (American English)? - English Language & Usage Stack Exchange
But if you’re asking merely about spelling, not pronunciation, that’s completely different. As I earlier mentioned in comments, the OED explains that this is because of the w‑ more than the ‑r, but this varies by speaker. So war, warden, warren, warranty, warrior, ward, reward, warble, ... More on english.stackexchange.com
🌐 english.stackexchange.com
April 13, 2024
Word, world, war can someone help me with the pronunciation? I can only pronounce the word "Word". "World" & "War" somehow became "Word" when I speak :(( where should I put my tongue or movement of the lips?
Word, world, war can someone help me with the pronunciation? I can only pronounce the word "Word". "World" & "War" somehow became "Word" when I speak :(( where should I put my tongue or movement of More on italki.com
🌐 italki.com
3
0
March 10, 2021
How to Pronounce war Phonetically (With Audio)?
How to say war in English? Pronunciation of war with 24 audio pronunciations, 39 synonyms, 1 meaning, 1 antonym, 15 translations, 81 sentences and more for war. More on howtopronounce.com
🌐 howtopronounce.com
1
May 17, 2021
How do you pronounce WAR?
🌐 r/baseball
119
45
September 27, 2022
🌐
Forvo
forvo.com › word › war
How to pronounce war in English - Definition and synonyms of war in English
Pronunciation by independentgentleman (Male from Germany) Sie war eine Kapitalistin.
🌐
ELSA
elsaspeak.com › en › learn-english › how-to-pronounce › war
How to Pronounce WAR in American English | ELSA Speak
Practice pronunciation of the word war with ELSA advanced technology and say war like Americans.
Find elsewhere
Top answer
1 of 3
4

In American English, 'r' can change the vowel before it. For many speakers, beard does not have quite the same vowel as either bid or bead, father does not have quite the same vowel as farther, and cord does not have quite the same vowel as cawed.

Depending on the speaker's dialect, the vowel of cord and war can be either /o/, /ɔ/, or somewhere in between. Further, it can have r-coloration, which means that the vowel is modified so that it sounds like the vowel and the consonant /r/ are being pronounced simultaneously; see this Wikipedia article on r-colored vowels. Thus, while some Americans have exactly the same vowel in war and talk, most don't.

2 of 3
4

Pronunciation

It’s because in America, unlike in Britain, the homophone-pair war, wore usually have the tense-o vowel /o/ of woe instead of the lax-o vowel /ɔ/ of talk. So wore and war sound like woe with an R tacked on the end here.

The same thing happens with words like lore and the homophone-triple pour, pore, poor: those all have the same tense /o/ vowel as low and Poe instead of the lax /ɔ/ vowel of law and paw. So lore is low plus an R not law plus an R, and pour, pore, poor is Poe plus an R not paw plus an R.

Warning: US /ɔ/ ≠ UK /ɔ/

Keep in mind that just like how the American /o/ phoneme is different phonetically from the British /o/ phoneme, the America /ɔ/ phoneme is also not the same phonetically as the British phoneme /ɔ/.

Our /ɔ/ is (usually) lower in the mouth than theirs is, so closer to phonetic [ɒ] than to phonetic [ɔ].

Spelling

But if you’re asking merely about spelling, not pronunciation, that’s completely different.

As I earlier mentioned in comments, the OED explains that this is because of the w‑ more than the ‑r, but this varies by speaker.

So war, warden, warren, warranty, warrior, ward, reward, warble, warn, warm, swarm, warship, dwarf, wharf, wart, thwart have tense /o/ for the majority of us who have neutralized the tense–lax contrast before /r/ and so simply always use the tense one (also called the "close" one, or sometimes the "long" one). In the UK, and in a very few remaining places in the US, the lax one is also possible there, but not for most of us.

In contrast, many speakers have lax /ɔ/ in want, water. A few have lax /ɔ/ in Lawrence, lawyer but most have tense /o/ in those two words. Plus some speakers even split homophone-pair warn, worn.

🌐
YouTube
youtube.com › watch
Learn to Pronounce WAR, WORE, and WHORE - American English Pronunciation Lesson #learnenglish - YouTube
Learn how to pronounce the English words WAR, WORE, and WHORE /wɔr, wɔr, hɔr/ correctly with this American English pronunciation lesson. Jennifer Tarle fr...
Published   November 30, 2016
🌐
EasyPronunciation
easypronunciation.com › en › english › word › war
War — Pronunciation: HD Slow Audio + Phonetic Transcription
How to pronounce 'war' in English. Normal and slow speed HD audio recordings and phonetic transcription written with International Phonetic Alphabet (IPA).
🌐
Pronunciation...
pronunciation.givemesomeenglish.com › home › pronunciation of the word “war”
War | GiveMeSomeEnglish!!! Pronunciation Portal
January 20, 2023 - The pronunciations that are presented ... English” but is more “International”). War — For this word: The “a” is pronounced as the long letter “o”....
🌐
italki
italki.com › en › post › bZqW6dfR27GYRXQVOmUF9r
Word, world, war can someone help me with the pronunciation? I can only pronounce the word "Word". "World" & "War" somehow became "Word" when I speak :(( where should I put my tongue or movement of
March 10, 2021 - “War”, although spelled with “a”, is pronounced with the open-O sound: /wɔr/. “Word” and “world” are absolutely *not* pronounced with any sort of “o” sound whatsoever.
🌐
HiNative
hinative.com › p › pr › pronounce › how do you pronounce 'w...
How do you pronounce 'war' and 'wall' differently? | HiNative
February 3, 2020 - I guess something like ㅝㅏ and ㅝㄹ. In UK when pronouncing war, the 'r' is silent while in US it is pronounced and stressed. Wall has the same beginning but you normally pronounce 'l' .
🌐
Quora
quora.com › what’s-the-pronunciation-difference-between-war-and-wall
What's the pronunciation difference between 'war' and 'wall'
Answer: These two sounds, at the end of words, take a lot of experimentation, instruction and feedback, but it can be done. I teach my students to pronounce war as [wōre] with an Ō vowel. Americans pronounce all their Rs so we work on the ...
🌐
YouTube
youtube.com › watch
How to Pronounce War - YouTube
http://www.bearstearnsbravo.comThis video shows you how to pronounce war. Learn the correct American English pronunciation of the term for a large-scale arme...
Published   August 24, 2012
🌐
YouTube
youtube.com › watch
How to Pronounce WAR, REWARD, WARNING, TOWARD - YouTube
Learn how to speak clearly, sound more natural and finally feel confident and comfortable in English. Join my FREE Own Your English training: https://www.cle...
Published   April 12, 2022