Cot-caught merger

In many parts of North America (about half the United States and nearly all of Canada)  and  sound the same. This is in addition to the father-bother merger, where and  sound the same. This means that caught and cot  (also father  and bother /ɒ/) have the same stressed vowel  In this accent  appears only followed by /r/: north, force.

This accent (which is not General American) is so prevalent that it is used in Merriam-Webster's Learner's Dictionary and in Cambridge Dictionaries Online for British English, US label. Note that Cambridge Dictionaries Online list two different American pronunciations, the one in Essential American English doesn't have the merger.

It can be conjectured that the spread of this merger via mass media has made some particular “modern” words to be pronounced with /ɑː/ even in dialects that have  For example "astronaut" pronounced as  in addition to

Other names for this merger (better for those who have it) are " LOT - THOUGHT merger" or " PALM - LOT - THOUGHT merger". There is an area in the United States (in New England) where "lot" and "thought" are merged as [ɒ] but "palm"/"father" is different (as [ɑ]). This means that strictly speaking " LOT - THOUGHT merger" and " PALM - LOT - THOUGHT merger" are different concepts.

The cot-caught merger is present also in Europe, but there the father-bother merger does not appear (similar to the area in New England mentioned above). The rest of this article is about the North American merge.

Comparison of phonemes
Sometimes we mark the CLOTH vowel with an asterisk, as follows:
 * *: These words are pronounced with /ɔː/ in General American.

Homophones
The cot-caught merger generates very few homophones.
 * bot (computer program; shortening of robot) - bought; collar - caller; cot - caught; don (put clothes on)/Don (nickname of Donald) - dawn/Dawn; stock - stalk; tot (very young child) - taught;

The PALM - LOT - THOUGHT merger generates even fewer homophones.
 * Bach (composer) - balk, baulk; la (musical note) - law; Ra (sun god) - raw

Phoneme /ɑː/ in the PALM - LOT - THOUGHT merger
This article is valid in an area in North America where the following words have the same phoneme vowel: "start", "palm", "spa", "lot", "thought" and "law".

Many people pronounce /ɑː/ and /ɑːr/ with different vowels (e.g. lodge as [lɑdʒ] and large as [lɑːrdʒ]); however since the difference is predictable there is no problem using the same symbol in both cases (e.g. /lɑːdʒ/ and /lɑːrdʒ/).

Merriam-Webster's Learner's Dictionary (MWLD) uses the cot-caught merger in its transcriptions. However, since it uses narrow notation, it uses three different symbols: /ɑː/ for "lot" and "lodge", /ɑɚ/ for "start" and "large" and and /ɑ/ for "sari".

Common words
Some common words which practice the pronunciation of /ɑː/ include the following:
 * with "a": father, iguana, llama, piñata, wad, wander, want, wash, wasp, watch, water
 * with "al": almost, already, also, alter, always, false, salt
 * "al" as /ɑː/: calm, chalk, palm, talk, walk
 * with "all": ball, call, fall, hall, mall, small, wall, wallet
 * with "ar": are, aren't, arm, art, article, bar, car, charge, dark, department, far, farm, hard, harm, large, market, park, part, party, regard, smart, star, start, warrant, warranty


 * with "o": Boston, chocolate, cloth, cost, follow, gone, got, hot, job, long, lost, lot, not, off, offer, office, often, on, possible, probably, problem, process, product, shop, song, strong, stop, top, wrong
 * with "oa": abroad, broad
 * with "ough": cough, ought, thought
 * past tense and past participle: bought, brought, fought, sought, thought


 * with "aw": dawn, draw, flaw, hawk, jaw, law, lawn, raw, saw, shawl, thaw, yawn
 * with "au": auction, August, Aussie, austerity, Australia, Austria, author, autumn, cause, clause, daughter, fault, launch, pause
 * past tense and past participle: caught - taught


 * /ɑː/ or /ʌ/: because, what
 * /ɑːj/ or /ɔɪ/: lawyer

Spelling anomalies
 * heart, knowledge

Homophones
 * bomb - balm; caller - collar; knot - not;

/ɑːr/ or /ɔːr/
See Decoding exercises: "orV" and "orrV"

Only the following five words are pronounced with /ɑː/ in this accent. Cambridge Dictonaries (“US” label) only agree in three words, marked with (*).


 * borrow,(*) morrow(*) (shortening of "tomorrow"), sorrow, sorry, tomorrow(*)

According to Wikipedia, the following words are pronounced with /ɑː/ by some speakers and with /ɔː/ by others. Only words marked with (*) have two pronunciations in Merriam-Webster's Learner's Dictionary; the rest have only /or/, equivalent to Teflpedia's /ɔːr/.


 * corridor, euphoric, foreign, forest, Florida,(*) historic, horrible, majority, minority, moral, orange,(*) Oregon, origin, porridge, priority, quarantine, quarrel, sorority, warranty, warren, warrior

Spanish
In Latin America American English is taught (the United Kingdom is far away). Spanish speakers tend to pronounce /ɑː/ according to the spelling. They will pronounce "palm" as [pam] and "lot" as.