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Extensions to the International Phonetic Alphabet

  (Redirected from Extensions to the IPA)

The extensions to the International Phonetic Alphabet, also extIPA symbols for disordered speech or simply extIPA (/ɛkˈstpə/)[1], are a set of letters and diacritics devised by the International Clinical Phonetics and Linguistics Association to augment the International Phonetic Alphabet for the phonetic transcription of disordered speech. Some of the symbols are occasionally used for transcribing features of normal speech.

Many sounds found only in disordered speech are indicated with diacritics, though an increasing number of dedicated letters are used as well. Special letters are included to transcribe the speech of people with lisps and cleft palates. The extIPA repeats several standard-IPA diacritics that are unfamiliar to most people but transcribe features that are common in disordered speech. These include preaspirationʰ◌⟩, linguolabial◌̼⟩, laminal fricatives [s̻, z̻] and ⟨*⟩ for a sound (segment or feature) with no available symbol (letter or diacritic). The novel transcription ⟨ɹ̈⟩ is used for an English molar-r, as opposed to ⟨ɹ̺⟩ for an apical r; these articulations are indistinguishable in sound and so are rarely identified in non-disordered speech.

Sounds not found in non-disordered speech include fricative nasals (a.k.a. nareal fricatives) and percussive consonants. Sounds sometimes found in the world's languages that do not have symbols in the IPA include denasals and fricatives that are simultaneously lateral and sibilant.



The full letters added by the extIPA are the following:

Lateral ʪ Voiceless grooved lateral alveolar fricative, [ɬ͡s] (a laterally lisped /s/, with simultaneous airflow through the sibilant groove in the tongue and across the side of the tongue) intended for a lateral lisp
ʫ Voiced grooved lateral alveolar fricative, [ɮ͡z] (a laterally lisped /z/)
Voiceless retroflex lateral fricative
l ᶚ Voiced retroflex lateral fricative
 ̬[2] Palatal lateral fricatives
 ̬[3] Velar lateral fricatives
Velo­pharyngeal ʩ ʩ̬ Velopharyngeal fricative (often occurs with a cleft palate)
  Voiceless velopharyngeal trill or 'snort'
Velo­dorsal k [4] Voiceless velodorsal plosive
ɡ Voiced velodorsal plosive
ŋ Velodorsal nasal
Pharyn­geal Q Voiceless upper-pharyngeal plosive
ɢ Voiced upper-pharyngeal plosive
Percussive ʬ Bilabial percussive (smacking lips)
ʭ Bidental percussive (gnashing teeth)
¡ Sublaminal lower-alveolar percussive (tongue slap)

The symbol ⟨¡⟩ is used with the alveolar click for [ǃ¡], an alveolar click with percussive release, a "cluck".

VoQS letters may also be used, as in ⟨ↀ͡r̪͆⟩ for a buccal interdental trill (a raspberry).


The extIPA has widened the use of some of the regular IPA symbols, such as ʰp for pre-aspiration, or for uvularization, as well as adding some new ones. Some of the extIPA diacritics are occasionally used for non-disordered speech, for example for the unusual airstream mechanisms of Damin.

One modification is the use of subscript parentheses around the phonation diacritics to indicate partial phonation; a single parenthesis at the left or right of the voicing indicates that it is partially phonated at the beginning or end of the segment. These conventions may be convenient for representing various voice onset times. Phonation diacritics may also be prefixed or suffixed rather than placed directly under the segment to represent relative timing.

Partial (de)voicing[5]
₍s̬₎ partial/central voicing of [s] ₍z̥₎ ⁽ʒ̊⁾ partial/central devoicing of [z], [ʒ]
₍s̬ initial voicing ₍z̥ initial devoicing
s̬₎ final voicing z̥₎ final devoicing
₍z̤₎ partial murmuring of [z] (etc.)
 ̬z pre-voiced [z] z ̬ post-voiced [z]
a ̰ [a] with a creaky offglide (etc.)

The transcriptions for partial voicing and devoicing may be used in either the sense of degrees of voicing or in the sense that the voicing is discontinuous. For the former, both parentheses indicate the sound is mildly (partially) voiced throughout, and single parentheses mean a partial degree of voicing at the beginning or end of the sound. For the latter, both parentheses mean the sound is (de)voiced in the middle, while the single parentheses mean complete (de)voicing at the beginning or end of the sound.

Altering the position of a diacritic relative to the letter indicates that the phonation begins before the consonant or vowel does or continues beyond it. The voiceless ring and other phonation diacritics can be used in the same way if needed. For example, ⟨p˳a⟩ indicates that voicelessness continues past the [p], equivalent to ⟨pʰa⟩.

Other extIPA diacritics are:

Airstream mechanism
p↓ Ingressive airflow ʘ↑ Egressive airflow[6]
[7] Unaspirated ʰp Pre-aspiration
n͋    v͋ (on a nasal letter) Nareal fricative [8] Velopharyngeal friction (turbulent airflow through the velopharyngeal port at the back of the nose)
(on an oral letter) nasal fricative escape (audible turbulent airflow through the nostrils, as with a nasal lisp) Denasal (as with a headcold; complements the nasal diacritic)
Articulatory strength
Strong articulation (not necessarily fortis) Weak articulation (not necessarily lenis)
v͆    t͆ (on a labial letter) Dentolabial n̪͆    h̪͆ (on a coronal letter) Interdental
(on a coronal letter) class-3 occlusion (tongue protrudes past upper teeth, as with a severe underbite) (on a glottal letter) bidental
s͇    f͇[9] (on a coronal letter) Alveolar[10] Labial spreading (complements the diacritics for rounding – see rounded vowel)
(on a labial letter) labioalveolar (class-2 occlusion, as with a severe overbite)
Whistled s̻ z̻ laminal fricatives (including lowered tongue tip)[11]
ɹ̈    ɹ̺ bunched-r (molar-r) and apical-r, respectively s͕    s͔ Offset to the left and right, respectively[12]
s͢θ Slurred/sliding articulation (a consonantal diphthong, moving from one articulation to another within the time of a single segment) p\p\p Stutter (reiterated articulation)[13]

Diacritics may be placed within parentheses as the voicing diacritics are above. For example, ⟨⁽m͊⁾⟩ indicates a partially denasalized [m].

Following a longstanding tradition of the IPA not specified on the regular IPA chart, any IPA or extIPA letter may be used in superscript form as a diacritic, to indicate the onset, release or 'flavor' of another letter. For example, ⟨k⟩ for [k] with a lateral-fricative release (similar to the velar lateral affricate [k͜], but with less frication), or ⟨dʫ⟩ for [d] with lateral plus central release. Combining diacritics can be added to superscript diacritics, such as ⟨tʰ̪͆⟩ for [t] with bidental aspiration.

The VoQS voice-quality symbols take IPA and extended-IPA diacritics, as well as several additional diacritics that are potentially available for the extIPA. At least the subscript dot for 'whisper' is sometimes found in IPA transcription,[14] though that diacritic is also commonly used for apical-retroflex articulation.

Prosodic notation and indeterminate soundsEdit

The Extended IPA has adopted bracket notation from conventions transcribing discourse. Parentheses are used to indicate mouthing (silent articulation), as in (ʃːː), a silent sign to hush. Parentheses are also used to indicate silent pauses, for example (...). Double parentheses indicate extraneous, as in ((2 syll.)) or ((2σ)) for two extraneous syllables, though the common convention outside speech pathology is for this to indicate obscured or unidentifiable sounds, as when one person talks over another.[15]

In the extIPA, unidentifiable sounds are instead circled.[16] An empty circle, ◯, is used for an indeterminate segment,  σ  an indeterminate syllable, Ⓒ indicates a segment identifiable only as a consonant, etc. Full capital letters are used as wild-cards for categories of sounds, and may be combined with IPA and extIPA diacritics. For example,   (a circled ) indicates an indeterminate voiceless plosive. IPA and extIPA letters may also be circled, to indicate that their identification is uncertain. For example, ⓚ indicates that the segment is 'probably' [k]. At least in handwriting, the circle may be elongated into an oval for longer strings of symbols.

Curly brackets with Italian musical terms are used for phonation and prosodic notation, such as [{falsetto ˈhɛlp falsetto}] and terms for the tempo and dynamics of connected speech. These are subscripted within a {curly brace} notation to indicate that they are comments on the intervening text. The VoQS conventions use similar notation for voice quality.

(.) Short pause (..) Medium pause (...) Long pause (1.2) 1.2-second pause
(ʃːː) Silent articulation ⸨2σ⸩ Extraneous noise
f Loud speech
[{f ˈlaʊd f}] ff Louder speech
[{ff ˈlaʊdɚ ff}]
p Quiet speech
[{p ˈkwaɪət p}] pp Quieter speech
[{pp ˈkwaɪətɚ pp}]
allegro Fast speech [{allegro ˈfæst allegro}] lento Slow speech [{lento ˈsloʊ lento}]
crescendo, rallentando, and other musical terms may also be used.
Unidentifiable/indeterminate sounds
segment consonant fricative glide/approximant
click liquid nasal plosive
rhotic sibilant tone/accent/stress vowel


Three rows appear in the extIPA chart that do not occur in the IPA chart: "fricative lateral + median" (simultaneous grooved and lateral frication), "fricative nasal" (a.k.a. nareal fricative) and "percussive". A denasal row is added here. Several new columns appear as well, though the linguolabial column is the result of a standard-IPA diacritic.

Consonants not appearing on the standard IPA chart
Plosive p̪ b̪ p͇ b͇ p͆ b͆ t̼ d̼ t̪͆ d̪͆ (k ɡ) Q ɢ
Denasal ɳ͊ ɲ͊ ŋ͊
Nasal n̪͆ (ŋ)
Fricative nasal m̥͋ m͋ n̥͋ n͋ ɳ̥͋ ɳ͋ ɲ̥͋ ɲ͋ ŋ̥͋ ŋ͋
Trill r̪͆  
Median fricative f͇ v͇ f͆ v͆ h̪͆ ɦ̪͆ θ̼ ð̼ θ̪͆ ð̪͆ θ͇ ð͇ ʩ ʩ̬
Lateral fricative[17] ɬ̼ ɮ̼ ɬ̪͆ ɮ̪͆ l ᶚ  ̬  ̬
Median+lateral fricative ʪ ʫ
Lateral approximant l̪͆
Percussive ʬ ʭ (¡)


  1. ^ Ball, Martin J. (1993). "Further to Articulatory Force and the IPA Revisions". Journal of the International Phonetic Association. 23 (1): 39–41. doi:10.1017/S0025100300004783.
  2. ^ ʎ⟩ with a belt
  3. ^ Small-capital .
  4. ^ The old IPA letter for a velar click, ⟨ʞ⟩, was used for a voiceless velodorsal plosive from 2008 to 2015.
  5. ^ The parentheses should appear under or over the letter, on either side of the diacritic, but that is not fully supported by Unicode. As of version 8.0, only paired parentheses under the letter, as in [s̬᪽] and [z̥᪽], are encoded.
  6. ^ The up-arrow for egressive airflow is no longer present in the 2016 extIPA chart, but is mentioned in the accompanying article.
  7. ^ distinct in Unicode from the superscript equals sign, ⟨⁼⟩
  8. ^ This diacritic conflicts with the occasional IPA use of a double tilde for a high degree of nasalization.
  9. ^ This diacritic conflicts with the occasional IPA use of a double macron for a highly retracted sound.
  10. ^ Normally in the IPA, a transcription with a coronal letter, such as [n], is assumed to be alveolar unless a diacritic is added to indicate otherwise (e.g. dental or post-alveolar). However, a speech pathologist may need to indicate whether the alveolar target is actually achieved, and so may overtly transcribe an alveolar nasal as [n͇].
  11. ^ The latter could be specified by doubling the diacritic for extra laminal [s̻̻], [z̻̻].
  12. ^ Although not specified by the extIPA, these are generally taken to refer to the interlocutor's left and right, not the speaker's.
  13. ^ used in the transcription of Damin
  14. ^ e.g. Laver (1994) Principles of Phonetics, CUP
  15. ^ Double parentheses have dedicated characters in Unicode: ⸨2 syll.⸩.
  16. ^ Unicode encodes a combining circle diacritic that will work with any IPA letter, but as of 2015 it is not widely included in fonts: σ⃝ for an unidentifiable syllable.
  17. ^ The dorsal lateral fricatives will not display unless you have an SIL font such as Gentium Plus installed.


  • Ball, Martin J.; Howard, Sara J.; Miller, Kirk (2018). "Revisions to the extIPA chart". Journal of the International Phonetic Association. 48 (2): 155–164. doi:10.1017/S0025100317000147.
  • Martin Ball, John Esling & B Craig Dickson (1995) "The VoQS system for the transcription of voice quality", Journal of the International Phonetic Association 25 (2): 71–80.
  • M Duckworth, G Allen, W Hardcastle & M Ball (1990) "Extensions to the International Phonetic Alphabet for the transcription of atypical speech", Clinical Linguistics and Phonetics 4: 273–280.
  • Barry Hesselwood & Sara Howard (2008) "Clinical Phonetic Transcription". In Ball et al. (eds.) The Handbook of Clinical Linguistics. Blackwell.
  • Martin Ball & Orla Lowry (2001, 2008) Methods in Clinical Phonetics, "Transcribing Disordered Speech".

External linksEdit