The Cot-Caught Merger

My brief look into this distinction that occurs between Canadian and (most of) American English

Spoken American and Canadian English are generally similar. What provokes interest in me, however, are in the few places where they do differ. One such phenomenon where we see such a difference is the cot-caught distinction.

There exist two specific sounds in North American English (NAE) that I’d say are in contention with one another. The same words often present any one of these two sounds in different accents. The sounds I’m speaking of are ‘ɑ’ and ‘ɒ’. Yet again, these IPA symbols would appear unintelligible to anyone unfamiliar with them so I’ll try to do my best to capture what exactly it is that they represent. In order to demonstrate these sounds as accurately as I can, I will be using the following words to represent each of them: ‘father’ and ‘thought’. Depending on where you are from in North America, you’re more or less going to pronounce those two words with one of the other of the aforementioned vowels (ɑ and ɒ).

Think of the sound ‘ɑ’ as the sound produced when you open your mouth wide as though you were to yawn, with your tongue in a resting position at the bottom of your mouth. It’s a very open ‘ah’ sound. As a result of the open mouth and the tongue resting at the mouth’s base, the technical term for this sound is ‘open back unrounded vowel’.

The sound ‘ɒ’ is exactly the same as ‘ɑ’, except that in pronouncing this vowel, one’s lips must be rounded. As a result, this sound is referred to as the ‘open back rounded vowel’. It can be transliterated intuitively as an ‘aw’ sound.

The interesting part comes about when analyzing different regions’ pronunciation of these two sounds. Consider pronouncing the following list of words:

• Don – Dawn

• Cot – Caught

• Pond – Pawned

To a native speaker of Standard Canadian English (SCE) such as myself, each of these pairs of words contain the exact same vowel sound: ‘ɒ’, AKA ‘aw’. However, to a speaker of Inland Northern American English (the stereotypical ‘Midwestern’ accent), the difference in the pronunciation of these pairs is like night and day! To them it would be obvious that ‘don’ is pronounced as ‘dɑn’ whereas ‘dawn’ is pronounced as ‘dɒn’. The same goes for a number of other dialects of North America, ranging from New York City English to African American Vernacular English.

It becomes even more nebulous when one finds that the cot-caught merger can go either way; in some accents both sounds are merged into ‘ɑ’ and other accents they’re merged into ‘ɒ’! For example, many Californians pronounce ‘cot’ and ‘caught’ with the ‘ɑ’ sound, whereas Bostonians and others pronounce both with the ‘ɒ’ sound.

In fact, one could say that North America is broadly split by the cot-caught merger. In the following image, the map of North America is shown as divided broadly into regions where the merger has taken place and where it hasn’t. Canada and the Western U.S. are primarily where the merger is present whereas the states of the Midwest, South, and Eastern U.S. are where the merger is absent.

I personally find this phenomenon to be fascinating. Most of us North American Anglophones do not, on a daily basis, distinguish between our accents – they are, after all, largely homogenized. However, it is when differences like this crop up that we can acknowledge the beauty and diversity that exists even among accents of the same general region. It is for this reason that I love linguistics.