How do you pronounce each of the following words? And is there another correct way to pronounce them?
adult, address, almond, amen, arctic, aunt, banal, Caribbean, diabetes, either, envelope, harassment, herb, homage, mayonnaise, neither, niche, nuclear, pajama, potato, produce (as in produce department), schedule, tomato, Uranus
These are all (to use a non-technical term) toilet-paper-roll words. You know how the toilet paper roll can go over the top or under the bottom, but most people will prefer one way — and may even hate the other way? Toilet-paper-roll words have two common pronunciations, but people tend to commit to one or the other… sometimes quite vehemently.
I'm not talking about "this way is British and that way is American." The above are all words you can hear both ways in the same part of America. Well, OK, I've tossed in a few famous British-American distinguishers: tomato, potato, and pajama. The Americans went with a pronunciation matching what would be expected from an English word spelled that way, and the Brits went with something closer to the pronunciation in the language we got the words from.
For another classic pair, either and neither, there are people on both sides of the Atlantic using each pronunciation, and both have some historical basis. We would expect it to be "ee" going by historical patterns, but the "eye" version came to be preferred in London, which made it the higher-class version.
Aunt is another one that's pronounced differently depending on where you're from: If you say it "ahnt" you're probably from Britain or one of just a couple parts of the U.S. (notably the Boston area). In fact, the "ant" pronunciation is the older one, but it shifted to "ahnt" in England after the colonies were settled. Those colonies that retained stronger ties with — and respect for — Britain acquired the "ahnt" version and have tended to keep it as a mark of distinction.
The truth is, most toilet-paper-roll word pronunciation differences come from Brits handling a word one way and Americans handling it another — and then the British pronunciation getting used in the U.S. as well (and sometimes vice versa). And for quite a few of them, it's because the British took a French word and re-pronounced it according to English spelling rules, while Americans preferred a pronunciation that sounded more French, even if the word is still heavily Anglicized.
In words like adult and address, the French influence is to put the stress on the last syllable (but the real French spellings are adulte and adresse). In envelope, the French influence is to say the first syllable like "on" rather than "en," but we say the rest of the word English-style. The French style for herb is to drop the h (but the French spell it herbe). Same with homage (but the French spell it hommage and say it to rhyme with garage — not the British way of saying garage, though). With niche, the American "neesh" version matches the French quite neatly, while the British style rhymes with itch. With banal, the longstanding British way was to say it like "bane-al," but saying it the French way is now back in vogue, even over there.
Another word that the British Anglicized from French is harass and its related noun harassment. They shifted the accent to the first syllable, sounding like "harris." The Americans preferred the French-style second-syllable stress, no doubt further encouraged by the double s. But the British style is becoming more popular with people who don't want to sound like they're saying "her ass" — sort of like how the British "urine-us" pronunciation of Uranus, based on the Latin and Greek stress pattern, is sometimes preferred by Americans who don't like how the American say-it-like-it-looks version sounds like "your anus."
Latin and Greek stresses and long vowels have also led to divisions, thanks to the history of the English language. If a vowel is "long" in the source language, the British have normally used the English "long" equivalent — which is so different from the Latin or Greek because our "long" vowels went through the Great Vowel Shift in the late medieval era. For example, we used to say long a as "ah" but it moved up to "eh," long e went from "eh" to "ee," and long i went from "ee" to "eye." So a word such as amen — which came from Hebrew by way of Latin — saw its long a change from "ah-men" to "eh-men." But everyone in other countries, including in a lot of music, still used "ah-men," so it didn't go away. It came to be the version typically used by the "higher" churches, while the more "popular" ones have gone with "eh-men." But it's not a sharp divide.
Likewise, the long e at the end of the Greek source of diabetes resulted in a final "ease" sound, but many people, especially in the U.S., have reduced it to "iss." But if, to try to stave off diabetes, you head to the produce department, how you say the name of it will be influenced by different precedents: The noun produce was originally stressed on the second syllable like the verb produce, and when the stress shifted, the o kept a "short" sound. But in the U.S., it gained a "long" sound to match all those other words that start with pro. Some people have gone another step and reduced the second vowel from the "you" sound to its "short" version, as in "us."
Ambiguous spelling is a common factor. Consider Caribbean. Even in the Caribbean, some people say the name with the stress on the first syllable, and some with the stress on the second. We do know that the version with the stress on the first syllable is the older one; the second-syllable-stress version likely gains traction from the double b in the spelling. But that pronunciation has been around long enough that it's established and accepted.
Before you say that the older version has to be the only correct one, perhaps you should know that that position commits you to dropping the l in falcon and almond — in both cases it was added later but is accepted now. Oh, and schedule? In English (which got it from Old French) it used to be cedule, not "sh" or "sk" but "s"… which is completely wrong now. A few centuries ago it was respelled and repronounced on the basis of the Latin schedula, which the French got it from.
And then there are some words that have gained common "wrong" pronunciations due to normal change processes over time — mainly speakers' tongues going with what is easier in their accent. The mayonn in mayonnaise gets leveled out to "man"; the arct in arctic gets simplified to "art"; and, perhaps most famously, in nuclear the tongue keeps the same overall movement pattern but shifts a consonant so there's a more even — and easier-to-say — alternation: "nucular." All of these attract scorn now.
But just remember this: If the words bright, thrill, and ask had their vowels and consonants in the same order as they were in Old English, we would now be saying them as "birght," "thirl," and — yes — "aks." Sometimes the "wrong" version sticks.