Inphonetics,vowel roundedness is the amount of rounding in thelips during the articulation of avowel. It islabialization of a vowel. When arounded vowel is pronounced, the lips form a circular opening, andunrounded vowels are pronounced with the lips relaxed. In most languages,front vowels tend to be unrounded, andback vowels tend to be rounded. However, some languages, such asFrench,German andIcelandic, distinguish rounded and unrounded front vowels of the sameheight (degree of openness), and others, likeVietnamese andTurkish, distinguishes rounded and unrounded back vowels of the same height.Alekano is unusual in having only unrounded vowels.[1]
In theInternational Phonetic Alphabet vowel chart, rounded vowels are the ones that appear on the right in each pair of vowels. There are also diacritics,U+0339 ◌̹COMBINING RIGHT HALF RING BELOW andU+031C ◌̜COMBINING LEFT HALF RING BELOW, to indicate greater and lesser degrees of rounding, respectively.Thus[o̜] has less rounding than cardinal[o], and[o̹] has more (closer to the rounding of cardinal[u]). These diacritics can also be used with unrounded vowels:[ɛ̜] is more spread than cardinal[ɛ], and[ɯ̹] is less spread than cardinal[ɯ].[2]
There are two types of vowel rounding:protrusion andcompression.[3][4][5] In protruded rounding, the corners of the mouth are drawn together and the lips protrude like a tube, with their inner surface visible. In compressed rounding, the corners of the mouth are drawn together, but the lips are also drawn together horizontally ("compressed") and do not protrude, with only their outer surface visible. That is, in protruded vowels the inner surfaces of the lips form the opening (thus the alternate termendolabial), whereas in compressed vowels it is the margins of the lips which form the opening (thusexolabial).Catford (1982, p. 172) observes that back and central rounded vowels, such as German/o/ and/u/, are typically protruded, whereas front rounded vowels such as German/ø/ and/y/ are typically compressed. Back or central compressed vowels and front protruded vowels are uncommon,[6] and a contrast between the two types has been found to be phonemic in only one instance.[7]
There are no dedicated IPA diacritics to represent the distinction, but the superscript IPA letter ⟨◌ᵝ⟩ or ⟨◌ᶹ⟩ can be used for compression[8] and ⟨◌ʷ⟩ for protrusion. Compressed vowels may be pronounced either with the corners of the mouth drawn in, by some definitions rounded, or with the corners spread and, by the same definitions, unrounded. The distinction may be transcribed ⟨ʉᵝuᵝ⟩ vs ⟨ɨᵝɯᵝ⟩ (or ⟨ʉᶹuᶹ⟩ vs ⟨ɨᶹɯᶹ⟩).[9]
The distinction between protruded[u] and compressed[y] holds for thesemivowels[w] and[ɥ] as well as labialization. InAkan, for example, the[ɥ] is compressed, as arelabio-palatalized consonants as inTwi[tɕᶣi̘] "Twi" andadwuma[adʑᶣu̘ma] "work", whereas[w] and simply labialized consonants are protruded.[10] In Japanese, the/w/ is compressed rather than protruded, paralleling the Japanese/u/. The distinction applies marginally to other consonants. InSouthern Teke, the sole language reported to have a phonemic/ɱ/, the labiodental sound is "accompanied by strong protrusion of both lips",[11] whereas the[ɱ] found as anallophone of/m/ before/f,v/ in languages such as English is not protruded, as the lip contacts the teeth along its upper or outer edge. Also, in at least one account ofspeech acquisition, a child's pronunciation ofclown involves a lateral[f] with the upper teeth contacting the upper-outer edge of the lip, but incrown, a non-lateral[f] is pronounced with the teeth contacting the inner surface of the protruded lower lip.[12]
Some vowels transcribed with rounded IPA letters may not be rounded at all. An example is/ɒ/, the vowel oflot, which inReceived Pronunciation has very little if any rounding of the lips. The "throaty" sound of the vowel is instead accomplished withsulcalization, a furrowing of the back of the tongue also found in/ɜː/, the vowel ofnurse.[13]
It is possible to mimic the acoustic effect of rounded vowels by narrowing the cheeks, so-called "cheek rounding", which is inherent in back protruded (but not front compressed) vowels. The technique is used by ventriloquists to mask the visible rounding of back vowels like[u].[14] It is not clear if it is used by languages with rounded vowels that do not use visible rounding.
The chart below lists all of the attested vowel position triads which contain both compressed and protruded rounding:
| Front | Near-front | Central | Near-back | Back | |
|---|---|---|---|---|---|
| Semivowel | jɥɥʷ | j̈ɥ̈ẅ[15][16] | ɰwᵝw | ||
| Close | iyyʷ | ɨÿʉ[17] | ɯuᵝu | ||
| Near-close | ɪʏʏʷ | ɪ̈ʏ̈ʊ̈ | ɯ̽ʊᵝʊ | ||
| Close-mid | eøøʷ | ɘø̈ɵ | ɤoᵝo | ||
| Mid | e̞ø̞ø̞ʷ | ||||
| Open-mid | ɛœœʷ |
The lip position of unrounded vowels may be classified into two groups:spread andneutral. Front vowels are usually pronounced with the lips spread, and the spreading becomes more significant as the height of the vowel increases.[18] Open vowels are often neutral, i.e. neither rounded nor spread, because the open jaw allows for limited rounding or spreading of the lips.[19] This is reflected in the IPA's definition of thecardinal[a], which is unrounded yet not spread either.[20]
Protruded rounding is the vocalic equivalent of consonantallabialization. Thus, rounded vowels and labialized consonants affect one another byphonetic assimilation: Rounded vowels labialize consonants, and labialized consonants round vowels.
In many languages, such effects are minor phonetic detail, but in others, they become significant. For example, inStandard Chinese, the vowel/ɔ/ is pronounced[u̯ɔ] after labial consonants,[citation needed] an allophonic effect that is so important that it is encoded inpinyin transliteration: alveolar/tu̯ɔ˥/[twó] (多;duō) 'many' vs. labial/pu̯ɔ˥/[pwó] (波;bō) 'wave'. InVietnamese, the opposite assimilation takes place: velar codas/k/ and/ŋ/ are pronounced as labialized[kʷ] and[ŋʷ] or evenlabial-velar[kp] and[ŋm], after the rounded vowels/u/ and/o/.[citation needed]
In theNorthwest Caucasian languages of the Caucasus and theSepik languages ofPapua New Guinea, historically rounded vowels have become unrounded, with the rounding being taken up by the consonant. Thus, Sepik[ku] and[ko] are phonemically/kwɨ/ and/kwə/.[citation needed] In the extinctUbykh,[ku] and[ko] were phonemically/kʷə/ and/kʷa/.[citation needed]
A few ancientIndo-European languages likeLatin hadlabialized velar consonants.[21]
Vowel pairs differentiated by roundedness can be found in someBritish dialects (such as theCardiff dialect,Geordie andPort Talbot English) as well as in GeneralSouth African English. They involve a contrastive pair ofclose-mid vowels, with the unrounded vowel being eitherSQUARE/ɛər/ or a monophthongalFACE/eɪ/ and the rounded counterpart beingNURSE/ɜːr/. Contrasts based on roundedness are rarely categorical in English and they may be enhanced by additional differences in height, backness or diphthongization.[22][23][24][25]
| Accent | Vowel | Notes | ||
|---|---|---|---|---|
| FACE | SQUARE | NURSE | ||
| Cardiff[26] | [ei] | [eː] | [øː] | SQUARE may be open-mid[ɛː].[27] |
| GeneralSAE[24] | [eɪ] | [eː] | [øː] | |
| Geordie[25] | [eː] | [ɛː] | [øː] | FACE may be diphthongal[ɪə~eɪ], whereas NURSE may be back[ɔː] or unrounded[ɪː~ɜː].[25][28] |
| Port Talbot[23] | [eː] | [ɛː] | [øː] | The accent does not feature thepane–pain merger.[29] |
In addition, contemporary Standard Southern British English as well asWestern Pennsylvania English contrastSTRUT withLOT mostly by rounding. An example of a minimal pairs isnut vs.not. The vowels are open-mid[ʌ,ɔ] in the former dialect and open[ɑ,ɒ] in the latter. In Western Pennsylvania English, theLOT class also includes theTHOUGHT class (seecot-caught merger) and thePALM one (seefather-bother merger). In addition,LOT may be longer thanSTRUT due to its being afree vowel:[ɒː]. In SSBE, these are all distinct andLOT is a checked vowel. InScottish English, the two vowels tend to be realized as[ʌ] and[ɔ], respectively. The latter often includes theTHOUGHT class as the cot-caught merger is common in Scotland. IfTHOUGHT is distinct, it is realized as[ɔ], whereasLOT is lowered to[ɒ] or raised to[o̞]. This means that whilenought[nɔʔ] contrasts withnut[nʌʔ] by rounding,not may have a different vowel[nɒʔ~no̞ʔ]. In addition, all three vowels are short in Scotland (seeScottish vowel length rule), unless followed by a voiced fricative whereTHOUGHT (andLOT, if they are merged) is long, as in England.[30][31][32]
| Accent | Vowel | Notes | ||
|---|---|---|---|---|
| STRUT | LOT | THOUGHT | ||
| Scottish English[30] | [ʌ] | [ɔ(ː)~ɒ~o̞] | [ɔ(ː)] | LOT often merges withTHOUGHT. |
| Standard Southern British English[32] | [ʌ] | [ɔ] | [o̞ː] | |
| Western Pennsylvania English[31] | [ɑ] | [ɒ(ː)] | TheLOT class also includesTHOUGHT andPALM. | |
General South African English is unique among accents of English in that it can feature up to three front rounded vowels, with two of them having unrounded counterparts.[24]
| Height | Unr. vowel | Rnd. vowel | Notes | ||
|---|---|---|---|---|---|
| lexical set | realization | lexical set | realization | ||
| Close | FLEECE | [iː] | GOOSE | [yː] | GOOSE may be central[ʉː]. |
| Close-mid | SQUARE | [eː] | NURSE | [øː] | |
| Open-mid | (unpaired) | GOAT | [œː] | GOAT may be diphthongal[œɤ̈]. | |
The potential contrast between the close-mid[øː] and the open-mid[œː] is hard to perceive by outsiders, making utterances such asthe total onslaught[ðəˈtœːtl̩ˈɒnsloːt] sound almost likethe turtle onslaught[ðəˈtøːtl̩ˈɒnsloːt].[34]
The dictionary definition ofendolabial at Wiktionary The dictionary definition ofexolabial at Wiktionary The dictionary definition ofunrounded at Wiktionary
