Editing Approximant

{{Short description|Type of speech sound}}
{{About|the concept in linguistics|the concept in mathematics|Continued fraction}}
{{Distinguish|Approximate}}
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{{Cleanup lang|date=September 2024}}{{IPA notice}}

'''Approximants''' are [[phone (phonetics)|speech sounds]] that involve the [[Speech organ|articulators]] approaching each other but not narrowly enough<ref>{{Harvcoltxt|Ladefoged|1975|p=277}}</ref> nor with enough articulatory precision<ref>{{Harvcoltxt|Martínez-Celdrán|2004|p=201}}, citing {{Harvcoltxt|Ladefoged|Maddieson|1996}}</ref> to create [[manner of articulation|turbulent airflow]]. Therefore, approximants fall between [[fricative consonant|fricatives]], which do produce a turbulent airstream, and [[vowel]]s, which produce no turbulence.<ref>{{Harvcoltxt|Martínez-Celdrán|2004|p=201}}</ref> This class is composed of sounds like {{IPA|[ɹ]}} (as in ''rest'') and [[semivowels]] like {{IPA|[j]}} and {{IPA|[w]}} (as in ''yes'' and ''west'', respectively), as well as [[Lateral consonant|lateral]] approximants like {{IPA|[l]}} (as in ''less'').<ref>{{Harvcoltxt|Martínez-Celdrán|2004|p=201}}</ref>

==Terminology==
Before [[Peter Ladefoged]] coined the term ''approximant'' in the 1960s,<ref>{{Harvcoltxt|Martínez-Celdrán|2004|p=201}}, pointing to {{Harvcoltxt|Ladefoged|1964|p=25}}</ref> the terms ''frictionless continuant'' and ''semivowel'' were used to refer to non-lateral approximants.

In [[phonology]], ''approximant'' is also a [[distinctive feature]] that encompasses all [[sonorant]]s except [[nasal consonant|nasals]], including [[vowel]]s, [[Tap consonant|tap]]s, and [[Trill consonant|trill]]s.<ref>{{Harvcoltxt|Hall|2007|p=316}}</ref>

==Semivowels==
{{Main|Semivowel}}

Some approximants resemble vowels in acoustic and articulatory properties and the terms ''[[semivowel]]'' and ''glide'' are often used for these non-syllabic vowel-like segments. The correlation between semivowels and vowels is strong enough that cross-language differences between semivowels correspond with the differences between their related vowels.<ref>{{Harvcoltxt|Ladefoged|Maddieson|1996|p=323}}, citing {{Harvcoltxt|Maddieson|Emmorey|1985}}</ref>

Vowels and their corresponding semivowels alternate in many languages depending on the phonological environment, or for grammatical reasons, as is the case with [[Indo-European ablaut]]. Similarly, languages often avoid configurations where a semivowel precedes its corresponding vowel.<ref>{{Harvcoltxt|Rubach|2002|p=680}}, citing {{Harvcoltxt|Kawasaki|1982}}</ref> A number of phoneticians distinguish between semivowels and approximants by their location in a syllable. Although he uses the terms interchangeably, {{Harvcoltxt|Montreuil|2004|p=104}} remarks that, for example, the final glides of English ''par'' and ''buy'' differ from French ''par'' ('through') and ''baille'' ('tub') in that, in the latter pair, the approximants appear in the [[syllable coda]], whereas, in the former, they appear in the [[syllable nucleus]]. This means that opaque (if not minimal) contrasts can occur in languages like [[Italian language|Italian]] (with the i-like sound of ''piede'' 'foot', appearing in the nucleus: {{IPA|[ˈpi̯ɛˑde]}}, and that of ''piano'' 'plan', appearing in the syllable onset: {{IPA|[ˈpjaˑno]}})<ref>{{Harvcoltxt|Montreuil|2004|p=104}}</ref> and Spanish (with a near minimal pair being ''abyecto'' {{IPA|[aβˈjekto]}} 'abject' and ''abierto'' {{IPA|[aˈβi̯erto]}} 'opened').<ref>{{Harvcoltxt|Saporta|1956|p=288}}</ref>
:{|class="wikitable"
|-
|+Approximant-vowel correspondences<ref>{{Harvcoltxt|Martínez-Celdrán|2004|p=202}}</ref><ref>{{Harvcoltxt|Ladefoged|Maddieson|1996|p=323}}</ref>
! Vowel
! Corresponding<br />approximant
! Place of <br />articulation
! Example
|-
| {{IPA link|i}} || {{IPA link|j}}** || [[Palatal consonant|Palatal]] || Spanish ''ampl'''í'''o'' ('I extend') vs. ''ampl'''ió''''' ('he extended')
|-
| {{IPA link|y}} || {{IPA link|ɥ}} || [[Labio-palatal consonant|Labialized palatal]] || French ''aig'''u''''' ('sharp') vs. ''aig'''u'''ille'' ('needle')
|-
| {{IPA link|ɯ}} || {{IPA link|ɰ}}** || [[Velar consonant|Velar]] || Korean '''음'''식 ('food') vs.  '''의'''사 ('doctor')
|-
| {{IPA link|u}} || {{IPA link|w}} || [[Labialized velar consonant|Labialized velar]] || Spanish continúo ('I continue') vs. continuó ('he/she/it continued') and ('you continued') used only in the formal treatment of 'usted'.
|-
| {{IPA link|ɑ}} || {{IPA link|ʕ̞}} || [[Pharyngeal consonant|Pharyngeal]] || {{Example needed|date=January 2010}}
|-
| {{IPA link|ɚ}} || {{IPA link|ɻ}} || [[Postalveolar consonant|Postalveolar]], [[Retroflex consonant|retroflex]]{{ref|Retroflex|*}} ||North American English ''wait'''er''''' vs. ''wait'''r'''ess''
|}

:{{note|Retroflex|*}} Because of the articulatory complexities of the American English rhotic, there is some variation in its phonetic description. A transcription with the IPA character for an [[alveolar approximant]] ({{IPA|[ɹ]}}) is common, though the sound is more [[postalveolar consonant|postalveolar]]. Actual retroflexion may occur as well and both occur as variations of the same sound.<ref>{{Harvcoltxt|Hallé|Best|Levitt|Andrea|1999|p=283}} citing {{Harvcoltxt|Delattre|Freeman|1968}}, {{Harvcoltxt|Zawadzki|Kuehn|1980}}, and {{Harvcoltxt|Boyce|Espy-Wilson|1997}}</ref> However, {{Harvcoltxt|Catford|1988|p=161f}} makes a distinction between the vowels of American English (which he calls "rhotacized") and vowels with "retroflexion" such as those that appear in [[Badaga language|Badaga]]; {{Harvcoltxt|Trask|1996|p=310}}, on the other hand, labels both as [[r-colored vowel|r-colored]] and notes that both have a lowered third [[formant]].<ref>Both cited in {{Harvcoltxt|Hamann|2003|pp=25–26}}</ref>
:{{note|Retroflex|**}} Because the vowels {{IPA|[i ɯ]}} are articulated with spread lips, spreading is implied for their approximant analogues, {{IPA|[j ɰ]}}. However, these sounds generally have little or no lip-spreading. The fricative letters with a lowering diacritic, {{angbr IPA|ʝ˕ ɣ˕}}, may therefore be justified for a neutral articulation between spread {{IPA|[j ɰ]}} and rounded {{IPA|[ɥ w]}}.<ref>John Esling (2010) "Phonetic Notation", in Hardcastle, Laver & Gibbon (eds) ''The Handbook of Phonetic Sciences'', 2nd ed., p. 699</ref>

In articulation and often diachronically, [[palatal consonant|palatal]] approximants correspond to [[front vowel]]s, [[velar consonant|velar]] approximants to [[back vowel]]s, and labialized approximants to [[rounded vowel]]s. In American English, the [[rhotic consonant|rhotic]] approximant corresponds to the rhotic vowel. This can create alternations (as shown in the above table).

In addition to alternations, glides can be inserted to the left or the right of their corresponding vowels when they occur next to a hiatus.<ref>{{Harvcoltxt|Rubach|2002|p=672}}</ref> For example, in [[Ukrainian language|Ukrainian]], medial {{IPA|/i/}} triggers the formation of an inserted {{IPA|[j]}} that acts as a syllable onset so that when the affix {{IPA|/-ist/}} is added to футбол ('football') to make футболіст 'football player', it is pronounced {{IPA|[futbo̞ˈlist]}}, but маоїст ('[[Maoist]]'), with the same affix, is pronounced {{IPA|[mao̞ˈ'''j'''ist]}} with a glide.<ref>{{Harvcoltxt|Rubach|2002|pp=675–676}}</ref> [[Dutch language|Dutch]] for many speakers has a similar process that extends to mid vowels:<ref>{{Harvcoltxt|Rubach|2002|pp=677–678}}</ref>
* ''bioscoop'' → {{IPA|[bi'''j'''ɔskoːp]}} ('cinema')
* ''zee'' + ''en'' → {{IPA|[zeː'''j'''ə(n)]}} ('seas')
* ''fluor'' → {{IPA|[fly'''ɥ'''ɔr]}} ('fluorine')
* ''reu'' + ''en'' → {{IPA|[rø'''ɥ'''ə(n)]}} ('male dogs')
* ''Rwanda'' → {{IPA|[ru'''ʋ'''andɐ]}} ('[[Rwanda]]')<ref name="Dutch">There is dialectal and allophonic variation in the realization of {{IPA|/ʋ/}}. For speakers who realize it as {{IPA|[ʋ]}}, {{Harvcoltxt|Rubach|2002|p=683}} postulates an additional rule that changes any occurrence of {{IPA|[w]}} from glide insertion into {{IPA|[ʋ]}}.</ref>
* ''Boaz'' → {{IPA|[bo'''ʋ'''as]}} ('[[Boaz]]')<ref name="Dutch"/>

Similarly, vowels can be inserted next to their corresponding glide in certain phonetic environments. [[Sievers' law]] describes this behaviour for [[Germanic languages|Germanic]].

Non-high semivowels also occur. In colloquial [[Nepali language|Nepali]] speech, a process of [[glide-formation]] occurs, where one of two adjacent vowels becomes non-syllabic; the process includes mid vowels so that {{IPA|[dʱo̯a]}} ('cause to wish') features a non-syllabic mid vowel.<ref>{{Harvcoltxt|Ladefoged|Maddieson|1996|pp=323–324}}</ref> Spanish features a similar process and even nonsyllabic {{IPA|/a/}} can occur so that ''ahorita'' ('right away') is pronounced {{IPA|[a̯o̞ˈɾita]}}.<ref>{{Harvcoltxt|Martínez-Celdrán|Fernández-Planas|Carrera-Sabaté|2003|pp=256–257}}</ref> It is not often clear, however, whether such sequences involve a semivowel (a consonant) or a diphthong (a vowel), and in many cases, it may not be a meaningful distinction.

Although many languages have [[central vowel]]s {{IPA|[ɨ, ʉ]}}, which lie between back/velar {{IPA|[ɯ, u]}} and front/palatal {{IPA|[i, y]}}, there are few cases of a corresponding approximant {{IPA|[ ȷ̈]}}. One is in the Korean diphthong {{IPA|[ ȷ̈i]}} or {{IPA|[ɨ̯i]}}<ref>{{Cite web |url=https://pantherfile.uwm.edu/iverson/www/kordiph.pdf |title=Ahn & Iverson (2006) |access-date=2010-12-31 |archive-url=https://web.archive.org/web/20110720114729/https://pantherfile.uwm.edu/iverson/www/kordiph.pdf |archive-date=2011-07-20 }}</ref> though it is more frequently analyzed as velar (as in the table above), and [[Mapudungun]] may be another, with three high vowel sounds, {{IPA|/i/}}, {{IPA|/u/}}, {{IPA|/ɨ/}} and three corresponding consonants, {{IPA|/j/}}, and {{IPA|/w/}}, and a third one is often described as a non-labialized voiced velar fricative; some texts note a correspondence between this approximant and {{IPA|/ɨ/}} that is parallel to {{IPA|/j/}}–{{IPA|/i/}} and {{IPA|/w/}}–{{IPA|/u/}}. An example is ''liq'' {{IPA|/ˈliɣ/}} ({{IPA|[ˈliɨ̯]}}?) ('white').<ref>Listen to a [http://www.logosdictionary.org/sound/mp/5119539_n.wav recording] {{webarchive |url=https://web.archive.org/web/20060226053417/http://www.logosdictionary.org/sound/mp/5119539_n.wav |date=February 26, 2006 }}</ref>
It has been noted that the expected symbols for the approximant correlates of {{IPA|[ɨ], [ʉ]}} are {{angbr IPA|ɉ, ɥ̶}}<ref>Martin Ball & Joan Rahilly (2011) The symbolization of central approximants in the IPA. ''Journal of the International Phonetic Association''. 41 (2), pp. 231–237</ref> or {{angbr IPA|ɉ, w̶}}.<ref>{{Cite book |last1=Ball |first1=Martin J. |title=Phonetics for communication disorders |last2=Müller |first2=Nicole |publisher=Psychology Press |year=2011 |isbn=978-0-8058-5363-6 |page=70}}</ref>

==Approximants versus fricatives==
In addition to less turbulence, approximants also differ from fricatives in the precision required to produce them.<ref>{{Harvcoltxt|Boersma|1997|p=12}}</ref> When emphasized, approximants may be slightly fricated (that is, the airstream may become slightly turbulent), which is reminiscent of fricatives. For example, the [[Spanish language|Spanish]] word ''ayuda'' ('help') features a palatal approximant that is pronounced as a fricative in emphatic speech.<ref>{{Harvcoltxt|Martínez-Celdrán|2004|p=204}}</ref> Spanish can be analyzed as having a meaningful distinction between fricative, approximant, and intermediate {{IPA|/ʝ ʝ˕ j/}}.<ref>Martínez-Celdrán, E. (2004) "Problems in the classification of approximants". ''Journal of the International Phonetic Association'', 34, 201–10</ref> However, such frication is generally slight and intermittent, unlike the strong turbulence of fricative consonants.

For places of articulation further back in the mouth, languages do not contrast voiced fricatives and approximants. Therefore, the IPA allows the symbols for the voiced fricatives to double for the approximants, with or without a lowering [[diacritic]].{{citation needed|date=June 2019}}

Occasionally, the glottal "fricatives" are called approximants, since {{IPA|[h]}} typically has no more frication than voiceless approximants, but they are often [[phonation]]s of the glottis without any accompanying manner or place of articulation.

==Central approximants==
Approximants with a dedicated IPA symbol are in bold.
*[[bilabial approximant]] {{IPA|[β̞]}} (usually transcribed {{angbr IPA|β}})<ref name="IPA">There have been repeated requests that the IPA created dedicated symbols for {{IPA|[β̞]}} and {{IPA|[ð̞]}} – typically modifications of the base letters such as [[rotated letter|turned]] {{IPA|⟨}}<big><sub><span style="{{Transform-rotate|180}}">{{IPA|β}}</span></sub></big>{{IPA|⟩}} and {{IPA|⟨}}<big><sub><span style="{{Transform-rotate|180}}">{{IPA|ð}}</span></sub></big>{{IPA|⟩}} or reversed <span style="{{mirrorH}}">{{angbr IPA|β}}</span> and <span style="{{mirrorH}}">{{angbr IPA|ð}}</span> – but so far the IPA has deemed that there is insufficient need for them.</ref>
*'''[[labiodental approximant]]''' {{IPA|[ʋ]}}
*[[dental approximant]] {{IPA|[ð̞]}} (usually transcribed {{angbr IPA|ð}})<ref name="IPA" />
*[[alveolar approximant|'''alveolar & post-alveolar approximant''']] {{IPA|[ɹ]}}
*'''[[retroflex approximant]]''' {{IPA|[ɻ&thinsp;]}} (a consonantal {{IPAblink|ɚ}})
*[[palatal approximant|alveolo-palatal approximant]]{{IPA|[ɹ̠ʲ]}} or {{IPA|[j˖]}}
*'''[[palatal approximant]]''' {{IPA|[j]}} (a consonantal {{IPAblink|i}})
*'''[[velar approximant]]''' {{IPA|[ɰ]}} (a consonantal {{IPAblink|ɯ}})
*[[uvular approximant]] {{IPA|[ʁ̞]}} (usually transcribed {{angbr IPA|ʁ}})
*[[pharyngeal approximant]] {{IPA|[ʕ̞]}} (a consonantal {{IPAblink|ɑ}}; usually transcribed {{angbr IPA|ʕ}})
*[[epiglottal approximant]] {{IPA|[ʢ̞]}} (usually transcribed {{angbr IPA|ʢ}})
*[[breathy-voiced glottal approximant]] {{IPA|[ɦ]}}
*[[creaky-voiced glottal approximant]] {{IPA|[ʔ̞]}}

==Lateral approximants==
In lateral approximants, the center of tongue makes solid contact with the roof of the mouth. However, the defining location is the side of the tongue, which only approaches the teeth, allowing free passage of air.
* [[Alveolar lateral approximant|'''voiced alveolar lateral approximant''']] {{IPA|[l]}}
* '''[[retroflex lateral approximant]]''' {{IPA|[ɭ]}}
* [[alveolo-palatal lateral approximant]] {{IPA|[l̠ʲ]}} or {{IPA|[ʎ̟]}} (usually transcribed {{angbr IPA|ȴ}})
* [[Palatal lateral approximant|'''voiced palatal lateral approximant''']] {{IPA|[ʎ]}}
* '''[[velar lateral approximant]]''' {{IPA|[ʟ]}}
* [[uvular lateral approximant]] {{IPA|[ʟ̠]}}

==Coarticulated approximants==
*[[Voiced retroflex approximant|Labialized retroflex approximant]] {{IPA|[ɻʷ]}}
*[[labial-palatal approximant|'''labialized palatal approximant''']] {{IPA|[ɥ]}} (a consonantal {{IPAblink|y}})
*'''[[labialized velar approximant]]''' {{IPA|[w]}} (a consonantal {{IPAblink|u}})
*[[Voiced uvular fricative|labialized uvular approximant]] {{IPA|[ʁʷ]}}

==Voiceless approximants==
'''Voiceless approximants''' are not recognized by all phoneticians as a discrete phonetic category. There are problems in distinguishing voiceless approximants from voiceless [[fricative]]s.

=== Phonetic characteristics ===
[[Fricative]] consonants are generally said to be the result of turbulent airflow at a place of articulation in the vocal tract.<ref>{{Harvcoltxt|Ashby|Maidment|2005|pp=56–7}}</ref> However, an audible voiceless sound may be made without this turbulent airflow: {{Harvcoltxt|Pike|1943}} makes a distinction between "local friction" (as in {{IPA|[s]}} or {{IPA|[z]}}) and "cavity friction" (as in voiceless vowels like {{IPA|[ḁ]}} and {{IPA|[ɔ̥]}}).<ref>{{Harvcoltxt|Pike|1943|pp=71, 138–9}}</ref> More recent research distinguishes between "turbulent" and "laminar" airflow in the vocal tract.<ref>{{Harvcoltxt|Shadle|2000|pp=37–8}}</ref> It is not clear if it is possible to describe voiceless approximants categorically as having laminar airflow (or cavity friction in Pike's terms) as a way of distinguishing them from fricatives. {{Harvcoltxt|Ball|Rahilly|1999}} write that "the airflow for voiced approximants remains laminar (smooth), and does not become turbulent. Voiceless approximants are rare in the languages of the world, but when they do occur the airflow is usually somewhat turbulent."<ref>{{Harvcoltxt|Ball|Rahilly|1999|pp=50–1}}</ref> Audible voiceless sounds may also be produced by means of turbulent airflow at the glottis, as in {{IPA|[h]}}; in such a case, it is possible to articulate an audible voiceless sound without the production of local friction at a supraglottal constriction. {{Harvcoltxt|Catford|1977}} describes such sounds, but classes them as [[sonorant]]s.<ref>{{Harvcoltxt|Catford|1977|pp=122–3}}</ref>

=== Distinctiveness ===
Voiceless approximants are rarely if ever distinguished phonemically from voiceless fricatives in the sound system of a language. {{Harvcoltxt|Clark|Yallop|1995}} discuss the issue and conclude "In practice, it is difficult to distinguish between a voiceless approximant and a voiceless fricative at the same place of articulation&nbsp;... there is no evidence that any language in the world makes such a distinction crucial."<ref>{{Harvcoltxt|Clark|Yallop|1995|p=48}}</ref>

=== Disagreement over use of the term ===
Voiceless approximants are treated as a phonetic category by (among others) {{Harvcoltxt|Ladefoged|Maddieson|1996}}, {{Harvcoltxt|Catford|1977}}, and {{Harvcoltxt|Bickford|Floyd|2006}}. However, the term ''voiceless approximant'' is seen by some phoneticians as controversial. It has been pointed out that if ''approximant'' is defined as a speech sound that involves the articulators approaching each other but not narrowly enough to create turbulent airflow, then it is difficult to see how a ''voiceless'' approximant could be audible.<ref>{{Harvcoltxt|Akamatsu|1992|p=30}}</ref> As [[John C. Wells]] puts it in his blog, "voiceless approximants are by definition inaudible&nbsp;... If there's no friction and no voicing, there's nothing to hear."<ref>{{cite web |last1=Wells |first1=J. C. |title=[h]: Fricative or approximant? |url=https://phonetic-blog.blogspot.com/2009/04/h-fricative-or-approximant.html |website=John Wells' Blog |date=7 April 2009 |access-date=23 December 2020}}</ref> A similar point is made in relation to frictionless continuants by {{Harvcoltxt|O'Connor|1973}}: "There are no voiceless frictionless continuants because this would imply silence; the voiceless counterpart of the frictionless continuant is the voiceless fricative."<ref>{{Harvcoltxt|O'Connor|1973|p=61}}</ref> {{harvcoltxt|Ohala|Solé|2010}} argue that the increased airflow arising from voicelessness alone makes a voiceless continuant a fricative, even if lacking a greater constriction in the oral cavity than a voiced approximant.<ref>{{Harvcoltxt|Ohala|Solé|2010|p=43}}</ref>

{{Harvcoltxt|Ladefoged|Maddieson|1996}} argue that [[Burmese language|Burmese]] and [[Standard Tibetan]] have voiceless lateral approximants {{IPA|[l̥]}} and [[Navajo language|Navajo]] and [[Zulu language|Zulu]] voiceless lateral fricatives {{IPAblink|ɬ}}, but also say that "in other cases it is difficult to decide whether a voiceless lateral should be described as an approximant or a fricative".<ref>{{Harvcoltxt|Ladefoged|Maddieson|1996|pp=198–9}}</ref> {{harvcoltxt|Asu|Nolan|Schötz|2015}} compared voiceless laterals in [[Estonian Swedish]], [[Icelandic language|Icelandic]], and [[Welsh language|Welsh]] and found that Welsh-speakers consistently used {{IPA|[ɬ]}}, that Icelandic-speakers consistently used {{IPA|[l̥]}}, and that speakers of Estonian Swedish varied in their pronunciation. They conclude that there is "a range of variants within voiceless laterals, rather than a categorical split between lateral fricatives and voiceless approximant laterals".<ref>{{Harvcoltxt|Asu|Nolan|Schötz|2015|p=5}}</ref>

=== Occurrence in Western American English ===
Voiceless lateral approximants can occur after voiceless stops as [[allophone]] of its voiced counterpart, especially after the [[voiceless velar plosive]] {{IPA|/k/}}, in [[Western American English]].<ref>{{Harvcoltxt|Grønnum|2005|p=154}}</ref>

==Nasalized approximants==
Examples are:
*[[nasal palatal approximant]] {{IPA|[j̃]}}
*[[nasal labialized velar approximant]] {{IPA|[w̃]}}
*[[voiceless nasal glottal approximant]] {{IPA|[h̃]}}

In [[Portuguese language|Portuguese]], the '''nasal glides''' {{IPA|[j̃]}} and {{IPA|[w̃]}} historically became {{IPA|/ɲ/}} and {{IPA|/m/}} in some words. In [[Edo language|Edo]], the nasalized allophones of the approximants {{IPA|/j/}} and {{IPA|/w/}} are nasal occlusives, {{IPA|[ɲ]}} and {{IPA|[ŋʷ]}}.

What are transcribed as nasal approximants may include non-syllabic elements of [[nasal vowel]]s or diphthongs.

==See also==
{{Wiktionary|approximant}}
* [[Liquid consonant]]
* [[List of phonetics topics]]
* [[Semivowel]]

== Notes ==
{{Reflist}}

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{{DEFAULTSORT:Approximant Consonant}}
[[Category:Manner of articulation]]
[[Category:Approximant consonants|*]]