I believe they may be using a non-rhotic dialect. Not all Englishes pronounce that R. I beleive they're asking why the vowel in "wo" is the vowel in "book" instead of the vowel in "god".
Woman was originally spelled wifmann, from wif meaning "female" and mann meaning "person". The f eventually became an m, making wimmann.
Wif was pronounced "weef". The "ee" vowel is pronounced close to the front of the mouth. Over the centuries, the pronunciation of wimman changed, the vowel moving farther back in the mouth from an "ee" to an "ih" (as in "little"), then farther back to an "ooh" (as in "book").
The reason it's not pronounced with an "aww" (as in "yawn") or an "ahh" (as in "thought") is that these vowels are made even farther back in the mouth, close to the throat. They're also made with the mouth farther open than "ee", "ih", or "ooh". The vowel may have drifted from "ee" over the centuries, but it did not drift far enough to reach "ahh".
It used to be pronounced the way we pronounce "women", but supposedly the W sound affected the singular woman to sound more like the vowel in "wool" than "will".
Why does it be the vowel in "wool" and not the vowel in "cough"? I've only ever seen the W sound explanation about its pronunciation, but the vowel in "will" be "wool" are pronounced in similar places of the mouths (similar "closed-ness" of the mouth), so it might have been a small move from one sound to another.
hh26 t1_j5ilk7p wrote
Because there is no R. War has an 'r' in it, which makes the "rrr" sound at the end. Woman consists of 'wo' and "man", so that's how you pronounce it.
There are a lot of weird and inconsistent words in the English language. This is not one of them.