The Colt-Cult merger?

I was once at a dinner party with some colleagues, and a co-worker of mine was explaining to another co-worker a story they had heard about the eclipse which had happened in 2016.

A: It turns out that they were actually in a cult.

B: A colt? Like a baby horse?

A: No, not a colt, a cult, with a leader.

B: Oh, you mean a cult!

What had happened in this exchange? Co-worker A pronounced 'cult' as [kolt], with a vowel similar to 'cold' [kold]. But B pronounced 'cult' with a low, unrounded vowel: [kʌlt], with the vowel of 'cut' [kʌt]. Moreover, co-worker B pronounced 'colt' and 'cult' differently: [kolt] and [kʌlt], while co-worker A pronounced the same: [kolt]. This is an example of a new merger I'm tentatively calling the 'colt-cult' merger (although I've also seen it called the hull-hole merger). This is when /ʌl/ and /ol/ merge to /ol/, so that words like 'colt', 'cult', 'hull', and 'hole' all have the same [o] vowel. The realization of the 'ul' vowel can be lower, so "culled" would be [kɔld] (and similar to old American 'called').

This seems to be a merger that happened on the phonological level, because before I started reading about English dialectology, I had no idea that "cult" and "colt" were supposed to have different vowel qualities. Perhaps "cult" had a slightly lower vowel, but to me they were similar enough that you could make a pun out of it. I recall watching an episode of Bones where the protagonist, Temperance Brennan, very clearly said "skull" [skʌl] with a low, back, unrounded vowel, and thinking that was odd. It turns out, historically, the odd one is me.

There are some particularities to this. All the people I know with this merger speak American English, but it's not limited to any region. Co-worker B was from Pennsylvania, whereas I am from Florida. The Americans I've met who have this pronunciation pronounce /ol/ without a diphthong. This is in contrast to /o/ anywhere else. This means "go" has a diphthong but "gold" has a monophthong.

While there are many historic vowel changes before /l/, this merger seems to be on-going because there isn't a lot of research or awareness on it. Information on it includes this uncited quote from Wikipedia, but about English English: "The hull–hole merger is a conditioned merger of /ʌ/ and /oʊ/ before /l/ occurring for some speakers of English English with l-vocalization. As a result, "hull" and "hole" are homophones as [hɔʊ]." The realization of this merger would certainly be quite different from the American one, because the American one retains /l/ in both situations. Labov, Ash, and Boberg's he Atlas of North American English (2006) also mentions that this is a merger in American English that might require more attention in the future, but don't discuss it in depth otherwise.

Wild Speculation on where it came from

Alright, so here comes some wild speculation completely off the top of my head on why this is happening. Don't quote me on this, because these aren't developed ideas. This is just some fun free association to think about what other sound changes might be related to this merger.

One interesting commonality between co-worker A and I is that we both have the cot-caught merger. This means that we do not use the [ɔ] vowel in words that used to have it, such as "bought", "caught," "caller", and "law." We instead use the [ɑ] vowel and put those words in the same category as "bot," "cot," "coller," and "la." If you are a North American and you also have the cot-caught merger, then you may not be familiar with which words have the /ɔ/ sound or what the /ɔ/ sound even is. [ɔ] is pronounced much lower and backer in the mouth than [ɑ] - I find it helps to imagine you're an aristocratic British man or some other character from Downton Abbey, and saying "law" with as low a vowel as you can muster. As a rule of thumb, words spelled with 'aw' (law, caw), 'au' (caught), and -all (ball, all) tend to have the /ɔ/ sound. Now, we are especially interested in the ones with an /l/, so words like "ball" and "caller." While there are many words with /ɔl/, there are relatively fewer words that are pronounced /ɑl/. This list from Wiktionary shows the dire state of words that rhyme with 'oll'. (Note that this excludes words that also have the 'oll' sound like 'acknowledge'):

• boll (in some pronunciations; see also -əʊl)
• coll
• doll
• gnoll
• knoll (in some pronunciations; see also -əʊl)
• lol
• loll
• moll
• noll
• pol
• poll (in some pronunciations; see also -əʊl)
• quoll
• troll (in some pronunciations; see also -əʊl)
• vol

This means that the cot-caught merger doesn't introduce as much ambiguity before /l/. Perhaps there might be some confusion between 'caller' and 'collar,' or 'mall' and 'moll,' but overall it's not the biggest deal. A curious result of this is that I've noticed that a lot of Americans who otherwise have the cot-caught merger will still keep [ɔ] before 'l'! So they'll pronounce 'caught' and 'cot' with the same vowel [kɑt], but 'all' will have a different vowel [ɔl]. And this vowel is normally a little higher, so it's [ol]. And then the kicker comes where words which used to have 'oll' start being pronounced with [ɔl]. This is anecdotal, but I've been told that there are people who pronounce 'acknowledge' as [əknɔlədʒ]. For some folks then, /ɔl/ is spreading and covering areas that used to be /ɑl/. (I do not have this pronunciation.)

So now we have /ɔl ~ ol/ as a strange special category. Some Americans still distinguish between "caller" and "collar" while having the cot-caught merger, but what about 'call' vs 'coal'? I haven't had the opportunity to ask yet, but it would be interesting to wonder if these people who keep /ɔl ~ ol/ might merger 'call' and 'coal'. And if that's the case, might the absorption of 'cult' and 'hull' into /ɔl ~ ol/ be related? The 'uh' /ʌ/ vowel is otherwise safe in American English, but remember that strange things happen before /l/. If 'call' might be re-analyzed to be part of the same lexical set as 'coal', perhaps 'cull' might be being moved in that direction as well. Why, I'm not entirely sure from a theoretical basis. And this probably doesn't even describe the majority of people with the 'colt-cult' merger. For the record, I pronounce all /ɔl/ words with /ɑl/, so this doesn't describe me. But it seems that something is happening where words are moving between the COAL, CALL, and COLLER lexical sets, and now the CULL lexical set is joining the game.

Now that this wild and unfounded speculation on my part is done, I would love to hear if you all have any ideas on what is phonologically motivating this change. Is it related to the cot-caught merger? Are there people without the merger who still merge 'colt' and 'cult'? Are you aware of any research relating to changes in back vowels before /l/ and how it could apply to this situation? I would love to hear!