Fricatives are consonants produced by forcing air through a narrow channel made by placing two articulators close together.
These may be the lower lip against the upper teeth, in the case of ; the back of the tongue against the soft palate, in the case of German  (the final consonant of Bach); or the side of the tongue against the molars, in the case of Welsh  (appearing twice in the name Llanelli).
This turbulent airflow is called frication.
A particular subset of fricatives are the sibilants.
When forming a sibilant, one still is forcing air through a narrow channel, but in addition, the tongue is curled lengthwise to direct the air over the edge of the teeth.
English , , , and  are examples of sibilants.
The usage of two other terms is less standardized: "Spirant" is an older term for fricatives used by some American and European phoneticians and phonologists.
"Strident" could mean just "sibilant", but some authors include also labiodental and uvular fricatives in the class.
Types
The airflow is not completely stopped in the production of fricative consonants.
In other words, the airflow experiences friction.
Sibilants
voiceless coronal sibilant, as in English sip
voiced coronal sibilant, as in English zip
voiceless dental sibilant
voiced dental sibilant
voiceless apical sibilant
voiced apical sibilant
voiceless predorsal sibilant (laminal, with tongue tip at lower teeth)Pountain (2014) Exploring the Spanish Language, p. 18
voiced predorsal sibilant (laminal)
voiceless postalveolar sibilant (laminal)
voiced postalveolar sibilant (laminal)
voiceless palato-alveolar sibilant (domed, partially palatalized), as in English ship
voiced palato-alveolar sibilant (domed, partially palatalized), as the si in English vision
voiceless alveolo-palatal sibilant (laminal, palatalized)
voiced alveolo-palatal sibilant (laminal, palatalized)
voiceless retroflex sibilant (apical or subapical)
voiced retroflex sibilant (apical or subapical)
All sibilants are coronal, but may be dental, alveolar, postalveolar, or palatal (retroflex) within that range.
However, at the postalveolar place of articulation, the tongue may take several shapes: domed, laminal, or apical, and each of these is given a separate symbol and a separate name.
Prototypical retroflexes are subapical and palatal, but they are usually written with the same symbol as the apical postalveolars.
The alveolars and dentals may also be either apical or laminal, but this difference is indicated with diacritics rather than with separate symbols.
Central non-sibilant fricatives
voiceless bilabial fricative
voiced bilabial fricative
voiceless labiodental fricative, as in English fine
voiced labiodental fricative, as in English vine
voiceless linguolabial fricative
voiced linguolabial fricative
voiceless dental non-sibilant fricative, as in English thing
voiced dental non-sibilant fricative, as in English that
voiceless alveolar non-sibilant fricative
voiced alveolar non-sibilant fricative
voiceless trilled fricative
voiced trilled fricative
voiceless palatal fricative
voiced palatal fricative
voiceless velar fricative
voiced velar fricative
voiceless palatal-velar fricative (articulation disputed)
voiceless uvular fricative
voiceless pharyngeal fricative
The IPA also has letters for epiglottal fricatives,
voiceless epiglottal fricative
voiced epiglottal fricative
with allophonic trilling, but these might be better analyzed as pharyngeal trills.
John Esling (2010) "Phonetic Notation", in Hardcastle, Laver & Gibbon (eds) The Handbook of Phonetic Sciences, 2nd ed., p 695.
voiceless velopharyngeal fricative (often occurs with a cleft palate)
voiced velopharyngeal fricative
Lateral fricatives
voiceless dental lateral fricative
voiced dental lateral fricative
voiceless alveolar lateral fricative
voiced alveolar lateral fricative
voiceless postalveolar lateral fricative (Mehri)
or extIPA  voiceless retroflex lateral fricative
or extIPA  Voiced retroflex lateral fricative (in Ao)
or  or extIPA  voiceless palatal lateral fricative (PUA )
or extIPA  voiced palatal lateral fricative (allophonic in Jebero)
or extIPA  voiceless velar lateral fricative (PUA )
or extIPA  voiced velar lateral fricative
The lateral fricative occurs as the ll of Welsh, as in Lloyd, Llewelyn, and Machynlleth (, a town), as the unvoiced 'hl' and voiced 'dl' or 'dhl' in the several languages of Southern Africa  (such as Xhosa and Zulu), and in Mongolian.
or  and  voiceless grooved lateral alveolar fricative (a laterally lisped  or ) (Modern South Arabian)
or  and  voiced grooved lateral alveolar fricative (a laterally lisped  or ) (Modern South Arabian)
IPA letters used for both fricatives and approximants
voiced uvular fricative
voiced pharyngeal fricative
No language distinguishes voiced fricatives from approximants at these places, so the same symbol is used for both.
For the pharyngeal, approximants are more numerous than fricatives.
A fricative realization may be specified by adding the uptack to the letters, .
Likewise, the downtack may be added to specify an approximant realization, .
(The bilabial approximant and dental approximant do not have dedicated symbols either and are transcribed in a similar fashion: .
However, the base letters are understood to specifically refer to the fricatives.)
Pseudo-fricatives
voiceless glottal transition, as in English hat
breathy-voiced glottal transition
In many languages, such as English, the glottal "fricatives" are unaccompanied phonation states of the glottis, without any accompanying manner, fricative or otherwise.
However, in languages such as Arabic, they are true fricatives.
In addition,  is usually called a "voiceless labial-velar fricative", but it is actually an approximant.
True doubly articulated fricatives may not occur in any language; but see voiceless palatal-velar fricative for a putative (and rather controversial) example.
{{anchor|Aspiration}}Aspirated fricatives
Fricatives are very commonly voiced, though cross-linguistically voiced fricatives are not nearly as common as tenuis ("plain") fricatives.
Other phonations are common in languages that have those phonations in their stop consonants.
However, phonemically aspirated fricatives are rare.
contrasts with  in Korean; aspirated fricatives are also found in a few Sino-Tibetan languages, in some Oto-Manguean languages, in the Siouan language Ofo ( and ), and in the (central?)
Chumash languages ( and ).
The record may be Cone Tibetan, which has four contrastive aspirated fricatives:  , , and .Guillaume Jacques 2011.
A panchronic study of aspirated fricatives, with new evidence from Pumi, Lingua 121.9:1518-1538 Nasalized fricatives
Phonemically nasalized fricatives are rare.
Umbundu has  and Kwangali and Souletin Basque have .
In Coatzospan Mixtec,  appear allophonically before a nasal vowel, and in Igbo nasality is a feature of the syllable; when  occur in nasal syllables they are themselves nasalized.Laver (1994: 255–256) Principles of Phonetics
----
Types of fricative{{efn|There are likely to be more aspirated, murmured and nasal fricatives than shown here. {{angbr IPA|s̄ ṣ ŝ}} are not IPA transcription.}}
Occurrence
Until its extinction, Ubykh may have been the language with the most fricatives (29 not including ), some of which did not have dedicated symbols or diacritics in the IPA.
This number actually outstrips the number of all consonants in English (which has 24 consonants).
By contrast, approximately 8.7% of the world's languages have no phonemic fricatives at all.Maddieson, Ian.
2008.
"Absence of Common Consonants".
In: Haspelmath, Martin & Dryer, Matthew S. & Gil, David & Comrie, Bernard (eds.)
The World Atlas of Language Structures Online.
Munich: Max Planck Digital Library, chapter 18.
Accessed on 2008-09-15.
This is a typical feature of Australian Aboriginal languages, where the few fricatives that exist result from changes to plosives or approximants, but also occurs in some indigenous languages of New Guinea and South America that have especially small numbers of consonants.
However, whereas  is entirely unknown in indigenous Australian languages, most of the other languages without true fricatives do have  in their consonant inventory.
Voicing contrasts in fricatives are largely confined to Europe, Africa, and Western Asia.
Languages of South and East Asia, such as Mandarin Chinese, Korean, the Dravidian and Austronesian languages, typically do not have such voiced fricatives as  and , which are familiar to many European speakers.
These voiced fricatives are also relatively rare in indigenous languages of the Americas.
Overall, voicing contrasts in fricatives are much rarer than in plosives, being found only in about a third of the world's languages as compared to 60 percent for plosive voicing contrasts.Maddieson, Ian.
"Voicing in Plosives and Fricatives", in Martin Haspelmath et al. (eds.)
The World Atlas of Language Structures, pp.
26–29.
Oxford: Oxford University Press, 2005. .
About 15 percent of the world's languages, however, have unpaired voiced fricatives, i.e. a voiced fricative without a voiceless counterpart.
Two-thirds of these, or 10 percent of all languages, have unpaired voiced fricatives but no voicing contrast between any fricative pair.Maddieson, Ian.
Patterns of Sounds.
Cambridge University Press, 1984. .
This phenomenon occurs because voiced fricatives have developed from lenition of plosives or fortition of approximants.
This phenomenon of unpaired voiced fricatives is scattered throughout the world, but is confined to nonsibilant fricatives with the exception of a couple of languages that have  but lack .
(Relatedly, several languages have the voiced affricate  but lack , and vice versa.)
The fricatives that occur most often without a voiceless counterpart are – in order of ratio of unpaired occurrences to total occurrences – , , ,  and .
Acoustics
Fricatives appear in waveforms as random noise caused by the turbulent airflow, upon which a periodic pattern is overlaid if voiced.
Fricatives produced in the front of the mouth tend to have energy concentration at higher frequencies than ones produced in the back.
The centre of gravity, the average frequency in a spectrum weighted by the amplitude, may be used to determine the place of articulation of a fricative relative to that of another.
See also
Apical consonant
Hush consonant
Laminal consonant
List of phonetics topics
Notes
References
External links
Fricatives in English
