Stop consonant

In phonetics, a stop, also known as a plosive or oral occlusive, is a consonant in which the vocal tract is blocked so that all airflow ceases.

The occlusion may be made with the tongue blade ([t], [d]) or body ([k], [ɡ]), lips ([p], [b]), or glottis ([ʔ]). Stops contrast with nasals, where the vocal tract is blocked but airflow continues through the nose, as in /m/ and /n/, and with fricatives, where partial occlusion impedes but does not block airflow in the vocal tract.


The terms stop, occlusive, and plosive are often used interchangeably. Linguists who distinguish them may not agree on the distinction being made. The terms refer to different features of the consonant. "Stop" refers to the airflow that is stopped. "Occlusive" refers to the articulation, which occludes (blocks) the vocal tract. "Plosive" refers to the release burst (plosion) of the consonant. Some object to the use of "plosive" for inaudibly released stops, which may then instead be called "applosives".

Either "occlusive" or "stop" may be used as a general term covering the other together with nasals. That is, 'occlusive' may be defined as oral occlusive (stops/plosives) plus nasal occlusives (nasals such as [m], [n]), or 'stop' may be defined as oral stops (plosives) plus nasal stops (nasals). Ladefoged and Maddieson (1996) prefer to restrict 'stop' to oral occlusives. They say,

what we call simply nasals are called nasal stops by some linguists. We avoid this phrase, preferring to reserve the term 'stop' for sounds in which there is a complete interruption of airflow.[1]

In addition, they use "plosive" for a pulmonic stop; "stops" in their usage include ejective and implosive consonants.[2]

If a term such as 'plosive' is used for oral obstruents, and nasals are not called nasal stops, then a stop may mean the glottal stop; 'plosive' may even mean non-glottal stop. In other cases, however, it may be the word 'plosive' that is restricted to the glottal stop. Note that, generally speaking, stops do not have plosion (a release burst). In English, for example, there are stops with no audible release, such as the /p/ in apt. However, pulmonic stops do have plosion in other environments.

In Ancient Greek, the term for stop was ἄφωνον (áphōnon),[3] which means "unpronounceable", "voiceless", or "silent", because stops could not be pronounced without a vowel. This term was calqued into Latin as mūta, and from there borrowed into English as mute.[4] Mute was sometimes used instead for voiceless consonants, whether stops or fricatives, a usage that was later replaced with surd, from Latin surdus "deaf" or "silent",[5] a term still occasionally seen in the literature.[6] For more information on the Ancient Greek terms, see Ancient Greek phonology § Terminology.

Common stops

All spoken natural languages in the world have stops,[7] and most have at least the voiceless stops [p], [t], and [k]. However, there are exceptions: Colloquial Samoan lacks the coronal [t], and several North American languages, such as the northern Iroquoian and southern Iroquoian languages (i.e., Cherokee), lack the labial [p]. In fact, the labial is the least stable of the voiceless stops in the languages of the world, as the unconditioned sound change [p][f] (→ [h] → Ø) is quite common in unrelated languages, having occurred in the history of Classical Japanese, Classical Arabic, and Proto-Celtic, for instance. Formal Samoan has only one word with velar [k]; colloquial Samoan conflates /t/ and /k/ to /k/. Ni‘ihau Hawaiian has [t] for /k/ to a greater extent than Standard Hawaiian, but neither distinguish a /k/ from a /t/. It may be more accurate to say that Hawaiian and colloquial Samoan do not distinguish velar and coronal stops than to say they lack one or the other.

See Common occlusives for the distribution of both stops and nasals.


In the articulation of the stop, three phases can be distinguished:

  • Catch: The airway closes so that no air can escape (hence the name stop).
  • Hold or occlusion: The airway stays closed, causing a slight pressure difference to build up (hence the name occlusive).
  • Release or burst: The closure is opened. The released airflow produces a sudden impulse causing an audible sound, or burst (hence the name plosive).

In many languages, such as Malay and Vietnamese, word-final stops lack a release burst, even when followed by a vowel, or have a nasal release. See no audible release.

Nasal occlusives are somewhat similar. In the catch and hold, airflow continues through the nose; in the release, there is no burst, and final nasals are typically unreleased across most languages.

In affricates, the catch and hold are those of a stop, but the release is that of a fricative. That is, affricates are stop–fricative contours.



Voiced stops are pronounced with vibration of the vocal cords, voiceless stops without. Stops are commonly voiceless, and many languages, such as Mandarin Chinese and Hawaiian, have only voiceless stops. Others, such as most Australian languages, are indeterminate: stops may vary between voiced and voiceless without distinction.


In aspirated stops, the vocal cords (vocal folds) are abducted at the time of release. In a prevocalic aspirated stop (a stop followed by a vowel or sonorant), the time when the vocal cords begin to vibrate will be delayed until the vocal folds come together enough for voicing to begin, and will usually start with breathy voicing. The duration between the release of the stop and the voice onset is called the voice onset time (VOT) or the aspiration interval. Highly aspirated stops have a long period of aspiration, so that there is a long period of voiceless airflow (a phonetic [h]) before the onset of the vowel. In tenuis stops, the vocal cords come together for voicing immediately following the release, and there is little or no aspiration (a voice onset time close to zero). In English, there may be a brief segment of breathy voice that identifies the stop as voiceless and not voiced. In voiced stops, the vocal folds are set for voice before the release, and often vibrate during the entire hold, and in English, the voicing after release is not breathy. A stop is called "fully voiced" if it is voiced during the entire occlusion. In English, however, initial voiced stops like /#b/ or /#d/ may have no voicing during the period of occlusion, or the voicing may start shortly before the release and continue after release, and word-final stops tend to be fully devoiced: In most dialects of English, the final /b/, /d/ and /g/ in words like rib, mad and dog are fully devoiced.[8] Initial voiceless stops, like the p in pie, are aspirated, with a palpable puff of air upon release, whereas a stop after an s, as in spy, is tenuis (unaspirated). When spoken near a candle flame, the flame will flicker more after the words par, tar, and car are articulated, compared with spar, star, and scar. In the common pronunciation of papa, the initial p is aspirated whereas the medial p is not.


In a geminate or long consonant, the occlusion lasts longer than in simple consonants. In languages where stops are only distinguished by length (e.g., Arabic, Ilwana, Icelandic), the long stops may be held up to three times as long as the short stops. Italian is well known for its geminate stops, as the double t in the name Vittoria takes just as long to say as the ct does in English Victoria. Japanese also prominently features geminate consonants, such as in the minimal pair 来た kita 'came' and 切った kitta 'cut'.

Note that there are many languages where the features voice, aspiration, and length reinforce each other, and in such cases it may be hard to determine which of these features predominates. In such cases, the terms fortis is sometimes used for aspiration or gemination, whereas lenis is used for single, tenuous, or voiced stops. Be aware, however, that the terms fortis and lenis are poorly defined, and their meanings vary from source to source.


Simple nasals are differentiated from stops only by a lowered velum that allows the air to escape through the nose during the occlusion. Nasals are acoustically sonorants, as they have a non-turbulent airflow and are nearly always voiced, but they are articulatorily obstruents, as there is complete blockage of the oral cavity. The term occlusive may be used as a cover term for both nasals and stops.

A prenasalized stop starts out with a lowered velum that raises during the occlusion. The closest examples in English are consonant clusters such as the [nd] in candy, but many languages have prenasalized stops that function phonologically as single consonants. Swahili is well known for having words beginning with prenasalized stops, as in ndege 'bird', and in many languages of the South Pacific, such as Fijian, these are even spelled with single letters: b [mb], d [nd].

A postnasalized stop begins with a raised velum that lowers during the occlusion. This causes an audible nasal release, as in English sudden. This could also be compared to the /dn/ cluster found in Russian and other Slavic languages, which can be seen in the name of the Dnieper River.

Note that the terms prenasalization and postnasalization are normally used only in languages where these sounds are phonemic: that is, not analyzed into sequences of stop plus nasal.

Airstream mechanism

Stops may be made with more than one airstream mechanism. The normal mechanism is pulmonic egressive, that is, with air flowing outward from the lungs. All languages have pulmonic stops. Some languages have stops made with other mechanisms as well: ejective stops (glottalic egressive), implosive stops (glottalic ingressive), or click consonants (lingual ingressive).


A fortis stop (in the narrow sense) is produced with more muscular tension than a lenis stop (in the narrow sense). However, this is difficult to measure, and there is usually debate over the actual mechanism of alleged fortis or lenis consonants.

There are a series of stops in the Korean language, sometimes written with the IPA symbol for ejectives, which are produced using "stiff voice", meaning there is increased contraction of the glottis than for normal production of voiceless stops. The indirect evidence for stiff voice is in the following vowels, which have a higher fundamental frequency than those following other stops. The higher frequency is explained as a result of the glottis being tense. Other such phonation types include breathy voice, or murmur; slack voice; and creaky voice.


The following stops have been given dedicated symbols in the IPA.

Symbols for stop consonants
p voiceless bilabial stop b voiced bilabial stop
t voiceless alveolar stop d voiced alveolar stop
ʈ voiceless retroflex stop ɖ voiced retroflex stop
c voiceless palatal stop ɟ voiced palatal stop
k voiceless velar stop ɡ voiced velar stop
q voiceless uvular stop ɢ voiced uvular stop
ʡ epiglottal stop
ʔ glottal stop


[p t k] voiceless,
aspirated word-initially, tenuis in clusters after s, word-final often with no audible release
[b d ɡ] unaspirated,
partially voiced word-initially, fully voiced intervocalically, fully devoiced when word-final
[ʔ] glottal stop, not as a phoneme in most dialects


Many subclassifications of stops are transcribed by adding a diacritic or modifier letter to the IPA symbols above.

Phonation and voice-onset time
t voiceless d voiced
tenuis aspirated
Airstream mechanism
t d pulmonic egressive
ejective ɗ implosive
! click
ⁿd prenasalized dⁿ nasally released
d⟩ with voicelessness diacritic
tense tt dd
tː dː

See also


  1. ^ Ladefoged, Peter; Maddieson, Ian (1996). The Sounds of the World's Languages. Oxford: Blackwell. p. 102. ISBN 0-631-19814-8.
  2. ^ Ladefoged, Peter; Maddieson, Ian (1996). The Sounds of the World's Languages. Oxford: Blackwell. pp. 77–78. ISBN 0-631-19814-8.
  3. ^ ἄφωνος. Liddell, Henry George; Scott, Robert; A Greek–English Lexicon at the Perseus Project
  4. ^ "mute". Oxford English Dictionary (3rd ed.). Oxford University Press. September 2005. (Subscription or UK public library membership required.)
  5. ^ surdus. Charlton T. Lewis and Charles Short. A Latin Dictionary on Perseus Project.
  6. ^ "surd". Oxford English Dictionary (3rd ed.). Oxford University Press. September 2005. (Subscription or UK public library membership required.)
  7. ^ König, W. (ed) dtv Atlas zur deutschen Sprache dtv 1994
  8. ^ Cruttenden, Alan Gimsons Pronunciation of English.

Further reading

External links

Alveolar stop

In phonetics and phonology, an alveolar stop is a type of consonantal sound, made with the tongue in contact with the alveolar ridge located just behind the teeth (hence alveolar), held tightly enough to block the passage of air (hence a stop consonant). The most common sounds are the stops [t] and [d], as in English toe and doe, and the voiced nasal [n]. The 2-D finite element mode of the front part of the midsagittal tongue can stimulate the air pressed release of an alveolar stop. Alveolar consonants in children’s productions have generally been demonstrated to undergo smaller vowel-related coarticulatory effects than labial and velar consonants, thus yielding consonant-specific patterns similar to those observed in adults.

The upcoming vowel target is adjusted to demand force and effort during the coarticulating process. More generally, several kinds are distinguished:

[t], voiceless alveolar stop

[d], voiced alveolar stop

[n], voiced alveolar nasal

[n̥], voiceless alveolar nasal

[tʼ], alveolar ejective

[ɗ ], voiced alveolar implosive

[ɗ̥ ] or [tʼ↓] voiceless alveolar implosive (very rare)Note that alveolar and dental stops are not always carefully distinguished. Acoustically, the two types of sounds are similar, and it is rare for a language to have both types.

If necessary, an alveolar consonant can be transcribed with the combining equals sign below ⟨◌͇⟩, as with ⟨t͇⟩ for the voiceless alveolar stop. A dental consonant can be transcribed with the combining bridge below ⟨t̪⟩, and a postalveolar consonant with the retraction diacritic, the combining minus sign below ⟨t̠⟩.

Bilabial stop

In phonetics and phonology, a bilabial stop is a type of consonantal sound, made with both lips (hence bilabial), held tightly enough to block the passage of air (hence a stop consonant). The most common sounds are the stops [p] and [b], as in English pit and bit, and the voiced nasal [m]. More generally, several kinds are distinguished:

[p], voiceless bilabial stop

[b], voiced bilabial stop

[m], voiced bilabial nasal

[m̥], voiceless bilabial nasal

[ɓ], voiced bilabial implosive

[pʼ], bilabial ejective (rare)

[ɓ̥] or [pʼ↓], voiceless bilabial implosive (very rare)

Checked tone

A checked tone, commonly known by the Chinese calque entering tone (simplified Chinese: 入声; traditional Chinese: 入聲; pinyin: rùshēng; literally: 'the tone of character 入'), is one of the four syllable types in the phonology in Middle Chinese. Although usually translated as "tone", a checked tone is not a tone in the phonetic sense but rather a syllable that ends in a stop consonant or a glottal stop. Separating the checked tone allows -p, -t, and -k to be treated as allophones of -m, -n, and -ng, respectively, since they are in complementary distribution. Stops appear only in the checked tone, and nasals appear only in the other tones. Because of the origin of tone in Chinese, the number of tones found in such syllables is smaller than the number of tones in other syllables. In Chinese phonetics, they have traditionally been counted separately.

For instance, in Cantonese, there are six tones in syllables that do not end in stops but only three in syllables that do so. That is why although Cantonese has only six tones, in the sense of six contrasting variations in pitch, it is often said to have nine tones.

Final voiceless stops and therefore the checked "tones" have disappeared from most Mandarin dialects, spoken in northern and southwestern China, but have been preserved in the southeastern branches of Chinese, such as Yue, Min, and Hakka.

Tones are an indispensable part of Chinese literature, as characters in poetry and prose were chosen according to tones and rhymes for their euphony. The use of language helps the reconstruction of the pronunciation of Old Chinese and Middle Chinese since the Chinese writing system is logographic, rather than phonetic.

Dental stop

In phonetics and phonology, a dental stop is a type of consonantal sound, made with the tongue in contact with the upper teeth (hence dental), held tightly enough to block the passage of air (hence a stop consonant).

Dental and alveolar stops are often conflated. Acoustically, the two types of sounds are similar, and it is rare for a language to have both types. The International Phonetic Alphabet does not provide separate symbols for dental stops, but simply uses the diacritic U+032A ◌̪ COMBINING BRIDGE BELOW attached to the corresponding alveolar symbol. As a result, it is common for researchers working in the majority of languages with only one type or the other to simply use the alveolar symbols indifferently for both types, unless they specifically want to call attention to the distinction.

The most common sounds are the stops [t̪] and [d̪] and the nasal [n̪]. More generally, several kinds are distinguished:

[t̪], voiceless dental stop

[d̪], voiced dental stop

[n̪], voiced dental nasal

[t̪ʼ], dental ejective

[ɗ̪ ], voiced dental implosive

Fulniô language

Fulniô, or Yatê, is a language isolate of Brazil, and the only indigenous language remaining in the northeastern part of that country. The two dialects, Fulniô and Yatê, are very close. The Fulniô dialect is used primarily during a three-month religious retreat.The language is also called Carnijó, and alternate spellings are Fornió, Furniô, Yahthe, and Iatê.

Jin Chinese

Jin (simplified Chinese: 晋语; traditional Chinese: 晉語; pinyin: jìnyǔ) is a group of Chinese dialects or languages spoken by roughly 63 million people in northern China. Its geographical distribution covers most of Shanxi province except for the lower Fen River valley, much of central Inner Mongolia and adjoining areas in Hebei, Henan, and Shaanxi provinces. The status of Jin is disputed among linguists: Some prefer to classify it as a dialect of Mandarin, but others set it apart as a closely related, but separate sister-language to Mandarin.

Labial–velar consonant

Labial–velar consonants are doubly articulated at the velum and the lips, such as [k͡p]. They are sometimes called "labiovelar consonants", a term that can also refer to labialized velars, such as the stop consonant [kʷ] and the approximant [w].

Lower Yangtze Mandarin

Lower Yangtze Mandarin (simplified Chinese: 下江官话; traditional Chinese: 下江官話; pinyin: xiàjiāng guānhuà) is one of the most divergent and least mutually-intelligible groups of Mandarin dialects, as it neighbours the Wu, Hui, and Gan groups of varieties of Chinese. It is also known as Jiang–Huai Mandarin (simplified Chinese: 江淮官话; traditional Chinese: 江淮官話; pinyin: jiānghuái guānhuà), named after the Yangtze (Jiang) and Huai Rivers. Lower Yangtze dialects are distinguished from most other Mandarin varieties by their retention of a final glottal stop in words that ended in a stop consonant in Middle Chinese.

During the Ming dynasty and the early Qing dynasty, the lingua franca of administration was based on Lower Yangtze dialects. During the 19th century, the base shifted to the Beijing dialect.

Nasal release

In phonetics, a nasal release is the release of a stop consonant into a nasal. Such sounds are transcribed in the IPA with superscript nasal letters, for example as [tⁿ] in English catnip [ˈkætⁿnɪp]. In English words such as sudden in which historically the tongue made separate contacts with the alveolar ridge for the /d/ and /n/, [ˈsʌdən], many speakers today make only one contact. That is, the /d/ is released directly into the /n/: [ˈsʌdⁿn̩]. Although this is a minor phonetic detail in English (in fact, it is commonly transcribed as having no audible release: [ˈkæt̚nɪp], [ˈsʌd̚n̩]), nasal release is more important in some other languages.

Palatal stop

In phonetics and phonology, a palatal stop is a type of consonantal sound, made with the body of the tongue in contact with the hard palate (hence palatal), held tightly enough to block the passage of air (hence a stop consonant). Note that a stop consonant made with the tip of the tongue curled back against the palate is called a retroflex stop.

Palatal stops are less common than velar stops or alveolar stops and do not occur in English. However, they are somewhat similar to the English postalveolar affricates [tʃ] and [dʒ], as in chat and jet, and occur in various European languages, such as Hungarian, Icelandic, and Irish.

The term "palatal stop" is sometimes used imprecisely to refer to postalveolar affricates, which themselves come in numerous varieties, or to other acoustically-similar sounds, such as palatalized velar stops.

The most common sound is the voiced nasal [ ɲ]. More generally, several kinds are distinguished:

[c], voiceless palatal stop

[ ɟ], voiced palatal stop

[ ɲ], voiced palatal nasal

[ ɲ̥], voiceless palatal nasal

[cʼ], palatal ejective (fairly rare)

[ ʄ ], voiced palatal implosive (fairly rare)

[ ʄ̥ ] or [cʼ↓] voiceless palatal implosive (very rare)

Pre-stopped consonant

In linguistics, pre-stopping, also known as pre-occlusion or pre-plosion, is a phonological process involving the historical or allophonic insertion of a very short stop consonant before a sonorant, such as a short [d] before a nasal [n] or a lateral [l]. The resulting sounds ([ᵈn, ᵈl]) are called pre-stopped consonants, or sometimes pre-ploded or (in Celtic linguistics) pre-occluded consonants, although technically [n] may be considered an occlusive/stop without the pre-occlusion.

A pre-stopped consonant behaves phonologically as a single consonant. That is, like affricates and trilled affricates, the reasons for considering these sequences to be single consonants lies primarily in their behavior. Phonetically they are similar or equivalent to stops with a nasal or lateral release.


Release may refer to:

Film release, the public distribution of a film

Legal release, a legal instrument

News release, a communication directed at the news media

Release (ISUP), a code to identify and debug events in ISUP signaling

Release (music), one part of the A(ttack)D(ecay)S(sustain)R(release) envelope of a musical note

Release (software), a distribution of a computer software in the software release life cycle

Release (phonetics), the opening of the closure of a stop consonant

Release, a bridge in thirty-two-bar form

Retroflex stop

In phonetics and phonology, a retroflex stop is a type of consonantal sound, made with the tongue curled back and in contact with area behind the alveolar ridge or with the hard palate (hence retroflex), held tightly enough to block the passage of air (hence a stop consonant). The point of contact is commonly either the tongue tip or tongue blade (the portion just behind the tip).Sometimes, however, the tongue is curled far enough back that the underside actually contacts the palate. That is known as a subapical retroflex stop and particularly occurs in the Dravidian languages of southern India. A stop consonant that is made with the body of the tongue in contact with the hard palate is called a palatal stop.

Retroflex stops are less common than velar stops or alveolar stops and do not occur in English. They sound somewhat like the English alveolar stops [t] and [d], but they have a more hollow quality. Retroflex stops are particularly common in the South Asian languages, such as Hindi and Tamil. Although they are fairly rare in European languages, they occur in Swedish and Norwegian.

The most common sounds are the stops [ʈ] and [ɖ]. More generally, several kinds are distinguished:

[ʈ], voiceless retroflex stop

[ɖ], voiced retroflex stop

[ʈʼ], retroflex ejective (rare)

[ᶑ], voiced retroflex implosive (extremely rare or nonexistent)

[ᶑ̥] or [ʈʼ↓] voiceless retroflex implosive (almost certainly nonexistent)

Saltillo (linguistics)

In Mexican linguistics, saltillo (Spanish, meaning "little skip") is the word for a glottal stop consonant, [ʔ]. The name was given by the early grammarians of Classical Nahuatl. In a number of other Nahuan languages, the sound cognate to the glottal stop of Classical Nahuatl is [h], and the term saltillo is applied to either pronunciation. The saltillo is often written with an apostrophe, though it is sometimes written ⟨h⟩ for either pronunciation, or ⟨j⟩ when pronounced [h]. The spelling of the glottal stop with an apostrophe-like character most likely originates from transliterations of the Arabic hamza. It has also been written with a grave accent over the preceding vowel in some Nahuatl works, following Horacio Carochi (1645).

The saltillo represents a phoneme in many other indigenous languages of the Americas and so its presence or absence can distinguish words. However, there is no saltillo in Standard Spanish, so the sound is often imperceptible to Spanish-speakers, and Spanish writers usually did not write it when transcribing Mexican languages: Nahuatl [ˈtɬeko] "in a fire" and [ˈtɬeʔko] "he ascends" were both typically written tleco, for example. Where saltillo is distinguished, the latter may be written tlehko or tleꞌko.


A semi-syllabary is a writing system that behaves partly as an alphabet and partly as a syllabary. The term has traditionally been extended to abugidas, but for the purposes of this article it will be restricted to scripts where some characters are alphabetic and others are syllabic.

Smooth breathing

The smooth breathing (Ancient Greek: ψιλὸν πνεῦμα, translit. psilòn pneûma; Greek: ψιλή psilí; Latin: spīritus lēnis) is a diacritical mark used in polytonic orthography. In ancient Greek, it marks the absence of the voiceless glottal fricative /h/ from the beginning of a word.

Some authorities have interpreted it as representing a glottal stop, but a final vowel at the end of a word is regularly elided (removed) when the following word starts with a vowel and elision would not happen if the second word began with a glottal stop (or any other form of stop consonant). In his Vox Graeca, W. Sidney Allen accordingly regards the glottal stop interpretation as "highly improbable".The smooth breathing ( ᾿ ) is written as on top of one initial vowel, on top of the second vowel of a diphthong or to the left of a capital and also, in certain editions, on the first of a pair of rhos. It did not occur on an initial upsilon, which always has rough breathing (thus the early name ὕ hy, rather than ὔ y).

The smooth breathing was kept in the traditional polytonic orthography even after the /h/ sound had disappeared from the language in Hellenistic times. It has been dropped in the modern monotonic orthography.

Unreleased stop

A stop with no audible release, also known as an unreleased stop or an applosive, is a stop consonant with no release burst: no audible indication of the end of its occlusion (hold). In the International Phonetic Alphabet, lack of an audible release is denoted with an upper-right corner diacritic (U+031A ◌̚ COMBINING LEFT ANGLE ABOVE (HTML ̚)) after the consonant letter: [p̚], [t̚], [k̚].Audibly released stops, on the other hand, are not normally indicated. If a final stop is aspirated, the aspiration diacritic ⟨◌ʰ⟩ is sufficient to indicate the release. Otherwise, the "unaspirated" diacritic of the Extended IPA may be employed for this: apt [ˈæp̚t˭].

Voice onset time

In phonetics, voice onset time (VOT) is a feature of the production of stop consonants. It is defined as the length of time that passes between the release of a stop consonant and the onset of voicing, the vibration of the vocal folds, or, according to other authors, periodicity. Some authors allow negative values to mark voicing that begins during the period of articulatory closure for the consonant and continues in the release, for those unaspirated voiced stops in which there is no voicing present at the instant of articulatory closure.

IPA topics

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