Screwed up the coding:
ETA: Heck, there’s even two threads here about it, and the second-r pronunciation seems to be more common, and a reasonable number of the “sure-bit” pronunciations are because SDMB posters are a pedantic bunch (note one poster’s reply that they are the only ones they know who pronounce it the way it’s spelled.)
Niche: Rhymes with “itch” and “rich”. Yes, I know that’s not the French pronunciation, and I’m usually a stickler for that sort of thing, but I don’t think I’ve ever heard the French way except from non-Americans.
Mature: With a “tch”, more like the “tu” is getting slurred, which is where I assume the common pronunciation came from. I’ve known a few people who pronounce it with a “t”, notably my high school football coach, but for whatever reason, it just sounds hoity toity, in the same way as a faux British accent.
Cache: It’s “cash”. I’ve rarely heard “cashay”, and at least one case was someone who had read and heard the words and didn’t realize they were the same word.
Adirondacks: I had to look this up. If I were to take a stab at it, it would be Ad-ur-RON-dax.
Fetish: I have never heard anything other than FEH-tish. How do you get to feetish?
Cthulhu: Close to KUH-thoo-loo. I will accept KUH-too-loo or slight variants, but it irritates me not to pronounce the th. I’ve heard See-thoo-loo and variants, and it makes me want to punch those people in the face. Seriously, you think the letter C is supposed to be said? Ugh.
Et cetera: et SET-ur-uh. I get where the “ex” pronunciation comes from, as its easier to say for some people. It’s every so slightly easier for me to say “et”, and it’s correct, so that’s what I say.
February: I think I’m the only person I know that says feh-BROO-air-ee. Most people around me ignore the first r, but at some point I decided I’d start pronouncing some of those ignored letters. For instance, I also say the l in folk. Both have been mentioned to me as being weird; I don’t care. The “bruh” variant irritates me.
Sherbet: Honestly, I didn’t know that “sherbert” was the variant and that “sherbet” was the original. I’ve only heard it without the second r a few times, and those were fairly recent, and I pegged it as a regional thing on their part. I haven’t had much reason to look at it spelled, so it’s not surprising. Also, around here, we put the letter r in some weird places, so it could just be a function of that. For instance, I grew up saying “warsh” for wash (and variants like washing machine and Washington). I’ve tried to fix it, but it still slips out sometimes. I’ll probably still keep using the second r.
It’s not crazy, but you said it was a regular occurrence. Other than the example given of “expresso,” which I argue is due not to regularization but false etymology, I cannot think of any other word that is regularized in such a manner. The only changes I can think of in an imported foreign word are those that occur due to either orthography or due to an inability to actually say the sounds in question. The pronunciation in question meets neither of these criteria.
I do not allege that “ex cetera” is not a common pronunciation. I question whether it is part of a larger pattern.
The thing about using IPA is that not everyone knows how to read it. Also, the symbols don’t always display properly.
So learn how to read it.
Seriously, I have seen more than a few reddit threads where people work themselves into fits because no one stopped to think that a like in merry and a like in marry wouldn’t mean anything to someone with the mary/merry/marry merger.
Niche: Nitch
Mature: Muh-CHOOR
Cache: Cash
Adirondacks: Addi-RON-dacks
Fetish: FEH-tish
Cthulhu: Kuh-THOOL-hu
Et cetera: Et-SET-er-ah
February: FEB-u-ary (yeah, I’m lazy)
Sherbet: SHER-bet
Good luck reading it on a phone. I just found out that phones don’t display the characters at all. I had a Doper recently tell me they couldn’t understand my post because they couldn’t see the IPA symbols.
And surely, as Doper, you can figure out how to indicate the merger without using IPA. I can even just respell the merger: MAIR-ree/MEH-ree/MA-ree. Or I can say, a as in ate, e as in met, and a as in apple.
The problem is not people not knowing IPA, but people not knowing about the merger at all. If you don’t know about the merger, you’re still probably going to use the wrong IPA. If /εr/ (ehr) and /er/ (air) sound the same to you, you’ll just use them interchangeably.
Knowing IPA is a poor substitute for knowing the actual language.
For everyone who can’t or doesn’t want to read the IPA, here’s what he said using the OP’s transcription system. (I’d include stress, but the poster didn’t, so I might be wrong):
[ul]
[li]nitch[/li][li]ma-chure[/li][li]cash[/li][li]add-urr-ahn-dacks[/li][li]fet-tish[/li][li]k’-thool-hoo [but see note about the glottal stop][/li][li]et-cetera[/li][li]Febuary[/li][li]shurr-bett[/li][/ul]
Also, AHunter: the “correct” pronunciation of Cthulhu is approximately [ˈqlʊ-hlʊ]*, where [hl] is also rather guttural, and the tongue in the [l] position throughout[sup]†[/sup]. The usual pronunciation (approved by the official website) is [kǝˈθulu].
[sup]†[/sup] The exact instructions can be found here.
Do you really think my honest question amounted to “mocking”? We are all giving our opinions, and most of us understand there are no “rights or wrongs” in this. If I question the reasons for someone’s pronunciation, and possibly an inconsistency, it’s only to understand, not to mock. And if there’s anything I don’t need, it’s a censor.
You obviously care about this a whole lot more than I do.
Robert Ripley presented these ten words as words that not one person in 100,000 can pronounce correctly. Can you?
CARIBBEAN
CHIC
COCAINE
CULINARY
DATA
GONDOLA
GRATIS
IMPIOUS
VERSION
VIKING
He added, “If you think so…look in the dictionary!”
Having a reasonable approximation as well is the best thing, really, at least for now. Or giving one when asked. I have a new phone today, an S4, and I can actually read the IPA in the above post, but on my S2 it comes up completely blank. I imagine it’s the same with lots of phones, and I know I’m not the only one who mostly uses their phone to post here.
Here’s the way I say them.
Niche: neesh or neech
Mature: ma-TOOR
Cache: Cash
Adirondacks: AD-uh-RON-dacks
Fetish: FEH-tish
Cthulhu: kuh-THOO-loo, though I’ve never actually spoken the name.
Et cetera: et SEH-ter-ah, like the king of Siam said it.
February: FEB-roo-AIR-ee
Sherbet: SHER-bet
…and I don’t care if I’m saying them “wrong.”
In addition,
I say all the syllables in VEJ-uh-tuh- bulls.
The day after TOOZ-day is WED-'nz-day, partly to help me remember how to spell it, and partly to remember Who it’s named for.
ASS-tuh-risk, as in, “I regret that I have but one asterisk for my country.”
I couldn’t have said it better. 
For me, it’s something along the lines of:
niche: niʃ
mature: mə 't͡ʃɹ̩
cache: kæʃ
Adirondacks: "æ dɹ̩ 'an dæks
fetish: 'fɛ tɪʃ
Cthulhu: kə 'θu: lu:
February: 'fɛ bɹu: "ɛɹ i
sherbet: 'ʃɹ̩ bət
One more vote for IPA, which is indispensible for discussions like this. That having been said, I’m sure I’ve gotten a lot of the transcriptions above wrong, especially with the vowels. (As I probably would have in any other system. IPA isn’t perfect for this sort of short, isolated word list, but it’s better than having to give a separate list of keywords like ‘t as in top’ or vague indications along the lines of, ‘like [vowel], but shorter’. The standardization is nice too; when I look up a pronunciation in an online dictionary, I often have to dig a bit to find out if, for example, ‘i’ denotes the standard IPA value as in machine or something like the diphthong in high.)
niche: /niːʃ/
mature: /məˈtjʊə/
cache: /kʰeɪʃ/
Adirondacks: /ˌædiːˈɹɒndæks/ (at a guess. I’d never heard of them before)
fetish: /ˈfɛtʰɪʃ/
Cthulhu: /ˈkθuːluː/
et cetera: /ˌɛtˈsɛtʰɹə/
February: /ˈfɛbjəɹiː/
sherbet: /ˈʃɜːbət/
IPA really ought to be taught in schools.
As for dougie_montie’s list:
Caribbean: /kʰəˈɹɪbiən/
chic: /ʃiːk/
cocaine: /kʰoʊˈkʰeɪn/
culinary: /ˈkʰʌlɪnˌɛɹiː/
data: /ˈdeɪtʰə/
gondola: /ˈgɒndələ/
gratis: /ˈgɹɑːtʰɪs/
impious: /ˌɪmˈpʰaɪəs/
version: /ˈvɜːʒən/
Viking: /ˈvaɪkʰɪŋ/
Okay, so you’re the one in 100,000.
I think you and I both know that your question was intended to shame someone who has a different pronunciation than you by implying their pronunciation is illogical.
Well, anyone who pronounces words differently than I do should be ashamed!
How I pronounce these:
CARIBBEAN: KAIR-uh-BEE-unn or Kuh-RIB-bee-un (interchangeably)
CHIC: Sheek
COCAINE: co-CAIN
CULINARY: KYOO-lin-ar-y
DATA: DAY-ta
GONDOLA: GON-duh-luh
GRATIS: GROT-is
IMPIOUS: im-PIE-us (oops, thought it was referring to imps, not piety. fixed)
VERSION: VER-zhun
VIKING: VIE-king
For someone who’s IPA impaired, can somebody post the pronunciations in the “regular” way so I can tell if I’m correct? 