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Changing voices: The impact of sound change

Do you pronounce 'glass' to rhyme with 'gas'? Do both syllables in 'transplant' contain the same vowel or do you use a short vowel in the first syllable and a long vowel in the second? Discover how a sound change originating 400 years ago created an important British pronunciation distinction.

Lexical sets

The phonetician, John Wells, introduced in his book, Accents of English (1982), the concept of using a single word to refer to the pronunciation of a particular group of English words. He calls these word-groups lexical sets and uses a key word, such as BATH to identify them. The BATH set is probably the most significant vowel in terms of differentiating speakers in England, but other important lexical sets include the STRUT vowel which occurs in words such as cup, mother, blood and young; the GOAT vowel in words such as soap, grow, rose and old and the NURSE vowel in words such as bird, work, herd, church and earn.

Settling local differences

Linguists use these lexical sets to describe the degree of difference between accents. For example, speakers on Teesside share a number of similarities with speakers on Tyneside. Quite often people from outside the North East find it difficult to distinguish between the two groups: the two areas are geographically close together and so speech in the two places is naturally relatively similar. Locals, however, will recognise a number of crucial differences between the two accents, most noticeably perhaps the pronunciation of words in the NURSE set (see above) and START and PALM sets – words such as car, sharp and large or half, father and drama.

Geordie versus Cockney

On the other hand most native English speakers can easily distinguish between someone from Tyneside and someone from London simply because different vowel sounds are used in several lexical sets. In fact most speakers in Newcastle upon Tyne would probably pronounce the vowels in all the sets mentioned here differently to Londoners. In general terms then, the further away two communities are from each other, the more the speech of their inhabitants differs. The differences can be measured by counting the number of lexical sets for which speakers from each area use a contrasting vowel.

The North-South divide

The BATH vowel refers to the pronunciation of the vowel in the word bath and other words that share that same vowel, such as laugh, ask and dance. The pronunciation of these words was pretty uniform in most parts of England until quite recently – a short vowel similar to the one most of us use in the word cat. This is still the pronunciation most commonly heard throughout the north of England and in much of the Midlands. For most speakers in this part of the country the only pronunciation difference between the words cat and cast is the presence or absence of an <s> sound. We can call this sound ‘a’.

One word, three pronunciations

In the south of England, however, most speakers now use a long vowel rather like the sound you are asked to produce when a doctor examines your throat. Speakers here use a completely different vowel in words like mat and mast. We can refer to the vowel they use in mast as the sound ‘ah’. Some speakers in East Anglia, the West Country and the South West use a pronunciation that lies somewhere between these two extremes: the same vowel as that used by northerners but of slightly longer duration. This pronunciation we can call the sound ‘aa’. The way a speaker in England pronounces the BATH vowel is extremely revealing and we can immediately deduce something about a person who pronounces maths to rhyme with baths or mass to rhyme with pass. Speakers in the north of England are sometimes described as having a flat-BATH accent, while speakers in the south have a broad-BATH accent.

Origins of the North-South divide

Research suggests that the shift in pronunciation of words in the BATH set has been extremely gradual. In monitoring an ongoing change – that is, one that is not yet complete for all speakers of a language – we can track how that change moves gradually across geographical space, leaving ‘relic’ areas where the older form persists and ‘innovative’ areas where a newer form has taken root. Linguists have traced the origins of the change in pronunciation of words in the BATH set to the 1600s. It is thought that some speakers in London began to lengthen the <a> sound before the consonant sounds <s>, <f> and <th> – words such as grass, laugh and path. At some point this newer pronunciation was also transferred to words where <a> is followed by the following combination of consonant sounds: <nt>, <ns>, <nch> and <nd> and in some cases <mpl> – words such as plant, dance, branch, demand and example.

The ripple effect

This new, slightly longer vowel is perhaps best understood as the pronunciation we associate with outbursts expressing pain or anger – a sound that is typically transcribed by cartoonists as 'aaagh'. This pronunciation, ‘aa’, gradually spread outwards from London and indeed remains common in the West Country and to a lesser degree in East Anglia. The only difference between this pronunciation and the northern pronunciation is one of added length. Some time later a further change occurred in London and the South East of England, where speakers began to pronounce the vowel much further back in the mouth – rather like the sound we are asked to produce when a doctor examines our throat. We hear this pronunciation, ‘ah’, in present-day RP and in much of the southern half of England. So, this second sound change has not yet taken place in many parts of the country, and it remains to be seen whether it will ever spread nationally. The map below, based on research by Clive Upton and John Widdowson, shows the distribution of the different types of pronunciation at the time of the Survey of English Dialects in the 1950s. It demonstrates very clearly how successive sound changes spread outwards from a centre rather like the ripple effect caused by dropping a stone in a pond. We can see that the most recent form of pronunciation, ‘ah’, had by the 1950s taken firm hold in the South East of England. It had begun to spread in all directions from London and the Home Counties, although there are examples of ‘aa’ to the immediate north and west of London. Click on a location on the BATH variation map to hear how speakers in different parts of the country now pronounce words in this set.

In most cases RP speakers and those in the South East of England have now adopted the new pronunciation with ‘ah’ for the vast majority of words in the BATH set, although there remain a number of words where pronunciation varies, such as plastic, transport and substantial. There are also pairs of words which illustrate how the newer pronunciation has not yet affected every potential BATH word – ample with ‘a’, but sample with ‘ah’, crass with ‘a’ but grass with ‘ah’, for instance. In addition there is the curious situation in parts of the north of England where some speakers pronounce the words master and plaster with ‘ah’, despite the fact they pronounce every other BATH word – including faster – with ‘a’.

  • Jonnie Robinson
  • Jonnie Robinson is Lead Curator for Spoken English at the British Library. He has worked on two nationwide surveys of regional speech, the Survey of English Dialects and BBC Voices, and is on the editorial team for the journal English Today. In 2010/11 he co-curated the British Library exhibition Evolving English: One Language, Many Voices. His latest publication Evolving English WordBank: a glossary of present-day English dialect and slang (2015) draws on sound recordings made by visitors to the exhibition.

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