Click consonants, orclicks, are speech sounds that occur asconsonants in many languages ofSouthern Africa and in three languages ofEast Africa. Examples familiar toEnglish-speakers are thetut-tut (British spelling) ortsk! tsk! (American spelling) used to express disapproval or pity (IPA[ǀ]), thetchick! used to spur on a horse (IPA[ǁ]), and theclip-clop! sound children make with their tongue to imitate a horse trotting (IPA[ǃ]). However, theseparalinguistic sounds in English are not full click consonants, as they only involve the front of the tongue, without the release of the back of the tongue that is required for clicks to combine with vowels and form syllables.
Anatomically, clicks areobstruents articulated with two closures (points of contact) in the mouth, one forward and one at the back. The enclosed pocket of air israrefied by a sucking action of the tongue (in technical terminology, clicks have alingual ingressive airstream mechanism). The forward closure is then released,[note 1] producing what may be the loudest consonants in the language, although in some languages such asHadza andSandawe, clicks can be more subtle and may even be mistaken forejectives.
Click consonants occur at six principal places of articulation. TheInternational Phonetic Alphabet (IPA) provides five letters for these places (there is as yet no dedicated symbol for the sixth).
The easiest clicks for English speakers are thedental clicks written with ⟨ǀ⟩. These are sharp (high-pitched) squeaky sounds made by sucking on the front teeth. A simple dental click is used in English to express pity or to shame someone, or to call a cat or other animal, and is writtentut! in British English andtsk! in American English. In many cultures around the Mediterranean a simple dental click is used for "no" in answer to a direct question. They are written with the letterc inZulu andXhosa.
Next most familiar to English speakers are thelateral clicks, which are written with ⟨ǁ⟩. They are also squeaky sounds, though less sharp than[ǀ], made by sucking on the molars on either side (or both sides) of the mouth. A simple lateral click is made in English to get a horse moving, and is conventionally writtentchick!. They are written with the letterx in Zulu and Xhosa.
Then there are thebilabial clicks, written with ⟨ʘ⟩. These are lip-smacking sounds, but often without the pursing of the lips found in a kiss, that occur in words in only a few languages.
The above clicks sound likeaffricates, in that they involve a lot of friction. The next two families of clicks are more abrupt sounds that do not have this friction.
With thealveolar clicks, written with ⟨ǃ⟩, the tip of the tongue is pulled down abruptly and forcefully from the roof of the mouth, sometimes using a lot of jaw motion, and making a hollowpop! like a cork being pulled from an empty bottle. Something like these sounds may be used for a 'clip-clop' sound as noted above. These sounds can be quite loud. They are written with the letterq in Zulu and Xhosa.
Thepalatal clicks, ⟨ǂ⟩, are made with a flat tongue that is pulled backward rather than downward, and are sharper cracking sounds than the[ǃ] clicks, like sharply snapped fingers. They are not found in Zulu but are very common in the San languages of southern Africa.
Finally, theretroflex clicks are poorly known, being attested from only a single language,Central !Kung. The tongue is curled back in the mouth, and they are both fricative and hollow sounding, but descriptions of these sounds vary between sources. This may reflect dialect differences. They are perhaps most commonly written ⟨‼⟩, but that is anad hoc transcription. The expected IPA letter is ⟨𝼊⟩ (⟨ǃ⟩ with retroflex tail), and the IPA supported the addition of that letter to Unicode.
Technically, these IPA letters transcribe only the forward articulation of the click, not the entire consonant. As theHandbook states,[1]
Since any click involves a velar or uvular closure [as well], it is possible to symbolize factors such as voicelessness, voicing or nasality of the click by combining the click symbol with the appropriate velar or uvular symbol:[k͡ǂɡ͡ǂŋ͡ǂ],[q͡ǃ].[2]
Thus technically[ǂ] is not a consonant, but only one part of the articulation of a consonant, and one may speak of "ǂ-clicks" to mean any of the various click consonants that share the[ǂ] place of articulation.[3] In practice, however, the simple letter ⟨ǂ⟩ has long been used as an abbreviation for[k͡ǂ], and in that role it is sometimes seen combined with diacritics for voicing (e.g. ⟨ǂ̬⟩ for[ɡ͡ǂ]), nasalization (e.g. ⟨ǂ̃⟩ for[ŋ͡ǂ]), etc. These differing transcription conventions may reflect differing theoretical analyses of the nature of click consonants, or attempts to address common misunderstandings of clicks.
The only non-African language known to have clicks as regular speech sounds isDamin, a ritual code once used by speakers ofLardil inAustralia. In addition, one consonant in Damin is theegressive equivalent of a click, using the tongue to compress the air in the mouth for an outward (egressive) "spurt".[5][6]
Once clicks are borrowed into a language as regular speech sounds, they may spread to native words, as has happened due tohlonipa word-taboo in theNguni languages. InGciriku, for example, the European loanwordtomate (tomato) appears ascumáte with a click[ǀ], though it begins with at in all neighbouring languages. It has also been argued that click phonemes have been adopted into some languages through the process ofhlonipha, women refraining from saying certain words and sounds that were similar to the name of their husband, sometimes replacing local sounds by borrowing clicks from a nearby language.[7]
Scattered clicks are found inideophones and mimesis in other languages, such asKongo/ᵑǃ/,Mijikenda/ᵑǀ/ and Hadza/ᵑʘʷ/ (Hadza does not otherwise have labial clicks). Ideophones often use phonemic distinctions not found in normal vocabulary.
English and many other languages may use bare click releases ininterjections, without an accompanying rear release or transition into a vowel, such as the dental "tsk-tsk" sound used to express disapproval, or the lateraltchick used with horses. In a number of languages ranging from the central Mediterranean to Iran,[8] a bare dental click release accompanied by tipping the head upwards signifies "no".Libyan Arabic apparently has three such sounds.[9] A voiceless nasalback-released velar click[ʞ] is used throughout Africa forbackchanneling. This sound starts off as a typical click, but the action is reversed and it is the rear velar or uvular closure that is released, drawing in air from the throat and nasal passages.
Lexical clicks occasionally turn up elsewhere. InWest Africa, clicks have been reported allophonically, and similarly in French and German, faint clicks have been recorded in rapid speech where consonants such as/t/ and/k/ overlap between words.[10] InRwanda, the sequence/mŋ/ may be pronounced either with an epenthetic vowel,[mᵊ̃ŋ], or with a light bilabial click,[m𐞵̃ŋ]—often by the same speaker.
Speakers ofGan Chinese fromNingdu county, as well as speakers of Mandarin from Beijing andJilin and presumably people from other parts of the country, produce flapped nasal clicks in nursery rhymes with varying degrees of competence, in the words for 'goose' and 'duck', both of which begin with/ŋ/ in Gan and until recently began with/ŋ/ in Mandarin as well. In Gan, the nursery rhyme is,
[tʰienitsʰakᵑǃ¡o] 天上一隻鵝 'a goose in the sky'
[tihaitsʰakᵑǃ¡a] 地下一隻鴨 'a duck on the ground'
[tʰienitsʰakᵑǃ¡a] 天上一隻鴨 'a duck in the sky'
[tihaitsʰakᵑǃ¡o] 地下一隻鵝 'a goose on the ground'
[ᵑǃ¡osaŋᵑǃ¡otʰan,ᵑǃ¡opʰauᵑǃ¡o] 鵝生鵝蛋鵝孵鵝 'a goose lays a goose egg, a goose hatches a goose'
[ᵑǃ¡asaŋᵑǃ¡atʰan,ᵑǃ¡apʰauᵑǃ¡a] 鴨生鴨蛋鴨孵鴨 'a duck lays a duck egg, a duck hatches a duck'
Occasionally other languages are claimed to have click sounds in general vocabulary. This is usually a misnomer forejective consonants, which are found across much of the world.
For the most part, the Southern AfricanKhoisan languages only useroot-initial clicks.[note 2] Hadza, Sandawe and severalBantu languages also allowsyllable-initial clicks within roots. In no language does a click close a syllable or end a word, but since the languages of the world that happen to have clicks consist mostly of CV syllables and allow at most only a limited set of consonants (such as a nasal or a glottal stop) to close a syllable or end a word,most consonants share the distribution of clicks in these languages.
Most languages of the Khoesan families (Tuu, Kxʼa and Khoe) have four click types:{ ǀǁǃǂ } or variants thereof, though a few have three or five, the last supplemented with eitherbilabial{ ʘ } orretroflex{ 𝼊 }. Hadza and Sandawe in Tanzania have three,{ ǀǁǃ }. Yeyi is the only Bantu language with four,{ ǀǁǃǂ }, while Xhosa and Zulu have three,{ ǀǁǃ }, and most other Bantu languages with clicks have fewer.
Like other consonants, clicks can be described using four parameters:place of articulation,manner of articulation,phonation (including glottalisation) andairstream mechanism. As noted above, clicks necessarily involve at least two closures, which in some cases operate partially independently: an anterior articulation traditionally represented by the special click symbol in the IPA—and a posterior articulation traditionally transcribed for convenience as oral ornasal, voiced or voiceless, though such features actually apply to the entire consonant. The literature also describes a contrast betweenvelar anduvular rear articulations for some languages.
In some languages that have been reported to make this distinction, such asNǁng, all clicks have a uvular rear closure, and the clicks explicitly described as uvular are in fact cases where the uvular closure is independently audible: contours of a click into a pulmonic or ejective component, in which the click has two release bursts, the forward (click-type) and then the rearward (uvular) component. "Velar" clicks in these languages have only a single release burst, that of the forward release, and the release of the rear articulation isn't audible. However, in other languages all clicks are velar – for example Hadza, or uvular – for example Xhosa; and a few languages, such asTaa, have a true velar–uvular distinction that depends on the place rather than the timing of rear articulation and that is audible in the quality of the vowel.
Regardless, in most of the literature the stated place of the click is the anterior articulation (called therelease orinflux), whereas the manner is ascribed to the posterior articulation (called theaccompaniment orefflux). The anterior articulation defines theclick type and is written with the IPA letter for the click (dental ⟨ǀ⟩, alveolar ⟨ǃ⟩, etc.), whereas the traditional term 'accompaniment' conflates the categories of manner (nasal, affricated), phonation (voiced, aspirated, breathy voiced, glottalised), as well as any change in the airstream with the release of the posterior articulation (pulmonic, ejective), all of which are transcribed with additional letters or diacritics, as in thenasal alveolar click, ⟨ǃŋ⟩ or ⟨ᵑǃ⟩ or—to take an extreme example—thevoiced (uvular) ejective alveolar click, ⟨ᶢǃ͡qʼ⟩.
The size of click inventories ranges from as few as three (inSesotho) or four (inDahalo), to dozens in theKxʼa andTuu (Northern and Southern Khoisan) languages.Taa, the last vibrant language in the latter family, has 45 to 115 click phonemes, depending on analysis (clusters vs. contours), and over 70% of words in the dictionary of this language begin with a click.[12]
Clicks appear morestop-like (sharp/abrupt) oraffricate-like (noisy) depending on their place of articulation: In southern Africa, clicks involving anapicalalveolar orlaminalpostalveolar closure are acoustically abrupt and sharp, like stops, whereaslabial,dental andlateral clicks typically have longer and acoustically noisier click types that are superficially more like affricates. In East Africa, however, the alveolar clicks tend to beflapped, whereas the lateral clicks tend to be more sharp.
The six places of articulation of clicks that have dedicated letters in theInternational Phonetic Alphabet (IPA) arelabial ⟨ʘ⟩,dental ⟨ǀ⟩,lateral ⟨ǁ⟩,palatal ("palato-alveolar") ⟨ǂ⟩,(post)alveolar ("retroflex") ⟨ǃ⟩ andretroflex, with the 'implicit' letter ⟨𝼊⟩. In most languages, the alveolar and palatal types involve an abrupt release; that is, they are sharp popping sounds with little frication (turbulent airflow). The labial, dental and lateral types, on the other hand, are typically noisy: they are longer, lip- or tooth-sucking sounds with turbulent airflow, and are sometimes called affricates. (This applies to the forward articulation; both may also have either an affricate or non-affricate rear articulation as well.) Theapical places,ǃ andǁ, are sometimes called "grave", because their pitch is dominated by low frequencies; whereas thelaminal places,ǀ andǂ, are sometimes called "acute", because they are dominated by high frequencies. (At least in theNǁng language andJuǀʼhoan, this is associated with a difference in the placement of the rear articulation: "grave" clicks areuvular, whereas "acute" clicks arepharyngeal.) Thus the alveolar click[kǃ] sounds something like a cork pulled from a bottle (a low-pitch pop), at least in Xhosa; whereas the dental click[kǀ] is like Englishtsk! tsk!, a high-pitched sucking on the incisors. The lateral clicks are pronounced by sucking on the molars of one or both sides. The labial click[kʘ] is different from what many people associate with a kiss: the lips are pressed more-or-less flat together, as they are for a[p] or an[m], not rounded as they are for a[w].
The most populous languages with clicks, Zulu and Xhosa, use the lettersc, q, x, by themselves and indigraphs, to write click consonants. Most Khoisan languages, on the other hand (with the notable exceptions ofNaro andSandawe), use a more iconic system based on thepipe⟨|⟩. (The exclamation point for the "retroflex" click was originally a pipe with a subscript dot, along the lines ofṭ, ḍ, ṇ used to transcribe the retroflex consonants of India.) There are also two main conventions for the second letter of the digraph as well: voicing may be written withg and uvular affrication withx, or voicing withd and affrication withg (a convention of Afrikaans). In two orthographies of Juǀʼhoan, for example, voiced/ᶢǃ/ is writteng! ordq, and/ᵏǃ͡χ/!x orqg. In languages without/ᵏǃ͡χ/, such as Zulu,/ᶢǃ/ may be writtengq.
^a ⟨ʞ⟩ was proposed as the IPA letter for a palatal click byDaniel Jones, but in his writing he called it 'velar', which was evidently misunderstood by other phoneticians. Replacement with⟨🡣⟩ was proposed byClement Doke,[13] and with ⟨𝼋⟩ byBeach.[14] (The former is not supported by Unicode, and is here substituted with an arrow.) Doke and Beach usedadditional letters for voiced and nasal clicks, but these did not catch on.
^b The labial and palatal clicks do not occur in written Bantu languages. However, the palatal clicks have been romanized in Naron,Juǀʼhõasi and !Xun,[which?] where they have been written⟨tc⟩,⟨ç⟩ and⟨qc⟩, respectively. In the 19th century, palatal clicks were sometimes written with the letter⟨v⟩, which may have been the source of the Doke letter⟨🡣⟩.
There are a few less-well-attested articulations. A reported subapical retroflex articulation ⟨𝼊⟩ in Grootfontein !Kung[note 3] turns out to be alveolar with lateral release, ⟨ǃ𐞷⟩; Ekoka !Kung has a fricated alveolar click with an s-like release, provisionally transcribed ⟨ǃ͡s⟩; and Sandawe has a "slapped" alveolar click, provisionally transcribed ⟨ǃ¡⟩ (in turn, the lateral clicks in Sandawe are more abrupt and less noisy than in southern Africa). However, the Khoisan languages are poorly attested, and it is quite possible that, as they become better described, more click articulations will be found.
Formerly when a click consonant was transcribed, two symbols were used, one for each articulation, and connected with a tie bar. This is because a click such as[ɢ͡ǀ] was analysed as a voiced uvular rear articulation[ɢ] pronounced simultaneously with the forward ingressive release[ǀ]. The symbols may be written in either order, depending on the analysis: ⟨ɢ͡ǀ⟩ or ⟨ǀ͡ɢ⟩. However, a tie bar was not often used in practice, and when the manner istenuis (a simple[k]), it was often omitted as well. That is, ⟨ǂ⟩ = ⟨kǂ⟩ = ⟨ǂk⟩ = ⟨k͡ǂ⟩ = ⟨ǂ͡k⟩. Regardless, elements that do not overlap with the forward release are usually written according to their temporal order: Prenasalisation is always written first (⟨ɴɢ͡ǀ⟩ = ⟨ɴǀ͡ɢ⟩ = ⟨ɴǀ̬⟩), and the non-lingual part of a contour is always written second (⟨k͡ǀʼqʼ⟩ = ⟨ǀ͡kʼqʼ⟩ = ⟨ǀ͡qʼ⟩).
However, it is common to analyse clicks as simplex segments, despite the fact that the front and rear articulations are independent, and to use diacritics to indicate the rear articulation and the accompaniment. At first this tended to be ⟨ᵏǀ,ᶢǀ,ᵑǀ⟩ for ⟨k͡ǀ,ɡ͡ǀ,ŋ͡ǀ⟩, based on the assumption that the rear articulation was velar; but as it has become clear that the rear articulation is often uvular or even pharyngeal even when there is no velar–uvular contrast, voicing and nasalisation diacritics more in keeping with the IPA have started to appear: ⟨ǀ̥,ǀ̬,ǀ̃,ŋǀ̬⟩ for ⟨ᵏǀ,ᶢǀ,ᵑǀ,ŋᶢǀ⟩.
Variation in the transcription of accompaniments
Tenuis
Aspirated
Voiced
Nasal
Delayed ("uvular")
True uvular
Tie bars
k͡ǀ
k͡ǀʰ
ɡ͡ǀ
ŋ͡ǀ
ǀ͡k,ǀ͡kʰ,ǀ͡ɡ,ǀ͡ŋ
q͡ǀ,ǀ͡q etc.
k͜ǀ
k͜ǀʰ
ɡ͜ǀ
ŋ͜ǀ
ǀ͜k,ǀ͜kʰ,ǀ͜ɡ,ǀ͜ŋ
q͜ǀ,ǀ͜q etc.
Digraphs
kǀ
kǀʰ
ɡǀ
ŋǀ
ǀk,ǀkʰ,ǀɡ,ǀŋ
qǀ,ǀq etc.
Superscripts
ᵏǀ
ᵏǀʰ
ᶢǀ
ᵑǀ
ǀᵏ,ǀᵏʰ,ǀᶢ,ǀᵑ
𐞥ǀ,ǀ𐞥 etc.
Diacritics
ǀ̥
ǀʰ
ǀ̬
ǀ̬̃
NA
NA
In practical orthography, the voicing or nasalisation is sometimes given the anterior place of articulation:dc forᶢǀ andmʘ forᵑʘ, for example.
In the literature on Damin, the clicks are transcribed by adding⟨!⟩ to the homorganic nasal:⟨m!, nh!, n!, rn!⟩.
Places of articulation are often called clicktypes, releases, orinfluxes, though 'release' is also used for the accompaniment/efflux. There are seven or eight known places of articulation, not counting slapped or egressive clicks. These are(bi)labial affricatedʘ, or "bilabial";laminal denti-alveolar affricatedǀ, or "dental";apical (post)alveolar plosiveǃ, or "alveolar";laminal palatal plosiveǂ, or "palatal";laminal palatal affricatedǂᶴ (known only fromEkoka !Kung);subapical postalveolar𝼊, or "retroflex" (only known fromCentral !Kung and possibly Damin); andapical (post)alveolar lateralǁ, or "lateral".
Languages illustrating each of these articulations are listed below. Given the poor state of documentation of Khoisan languages, it is quite possible that additional places of articulation will turn up. No language is known to contrast more than five.
Aside from/ʘ↑/, which is not technically a click, all are nasal.
Extra-linguistically,Coatlán Zapotec ofMexico uses alinguolabial click,[ǀ̼ʔ], asmimesis for a pig drinking water,[16] and several languages, such asWolof, use avelar click[ʞ], long judged to be physically impossible, forbackchanneling and to express approval.[17] An extended dental click with lip pursing or compression ("sucking-teeth"), variable in sound and sometimes described as intermediate between[ǀ] and[ʘ], is found across West Africa, the Caribbean and into the United States.
The exact place of the alveolar clicks varies between languages. The lateral, for example, is alveolar in Khoekhoe but postalveolar or even palatal in Sandawe; the central is alveolar in Nǀuu but postalveolar in Juǀʼhoan.[18]
The terms for the click types were originally developed by Bleek in 1862.[19] Since then there has been some conflicting variation. However, apart from "cerebral" (retroflex), which was found to be an inaccurate label when true retroflex clicks were discovered, Bleek's terms are still considered normative today. Here are the terms used in some of the main references.
The dental, lateral and bilabial clicks are rarely confused, but the palatal and alveolar clicks frequently have conflicting names in older literature, and non-standard terminology is fossilized in Unicode. However, since Ladefoged & Traill (1984) clarified the places of articulation,[22] the terms listed under Vossen (2013) in the table above have become standard, apart from such details as whether in a particular languageǃ andǁ are alveolar or postalveolar, or whether the rear articulation is velar, uvular or pharyngeal, which again varies between languages (or may even be contrastive within a language).
Click manners are often called clickaccompaniments oreffluxes, but both terms have met with objections on theoretical grounds.
There is a great variety of click manners, both simplex and complex, the latter variously analysed as consonantclusters orcontours. With so few click languages, and so little study of them, it is also unclear to what extent clicks in different languages are equivalent. For example, the[ǃkˀ] of Khoekhoe,[ǃkˀ~ŋˀǃk] of Sandawe and[ŋ̊ǃˀ~ŋǃkˀ] of Hadza may be essentially the same phone; no language distinguishes them, and the differences in transcription may have more to do with the approach of the linguist than with actual differences in the sounds. Such suspected allophones/allographs are listed on a common row in the table below.
Some Khoisan languages aretypologically unusual in allowing mixedvoicing in non-click consonant clusters/contours, such as̬d̥sʼk͡x, so it is not surprising that they would allow mixed voicing in clicks as well. This may be an effect of epiglottalised voiced consonants, because voicing is incompatible with epiglottalisation.
As do other consonants, clicks vary inphonation. Oral clicks are attested with four phonations:tenuis,aspirated,voiced andbreathy voiced (murmured). Nasal clicks may also vary, with plain voiced, breathy voiced / murmured nasal, aspirated and unaspirated voiceless clicks attested (the last only in Taa). The aspirated nasal clicks are often said to have 'delayed aspiration'; there is nasal airflow throughout the click, which may become voiced between vowels, though the aspiration itself is voiceless. A few languages also have pre-glottalised nasal clicks, which have very brief prenasalisation but have not been phonetically analysed to the extent that other types of clicks have.
All languages have nasal clicks, and all butDahalo andDamin also have oral clicks. All languages but Damin have at least one phonation contrast as well.
Clicks may be pronounced with a third place of articulation, glottal. Aglottal stop is made during the hold of the click; the (necessarily voiceless) click is released, and then the glottal hold is released into the vowel. Glottalised clicks are very common, and they are generally nasalised as well. The nasalisation cannot be heard during the click release, as there is no pulmonic airflow, and generally not at all when the click occurs at the beginning of an utterance, but it has the effect of nasalising preceding vowels, to the extent that the glottalised clicks of Sandawe and Hadza are often described as prenasalised when in medial position. Two languages,Gǀwi andYeyi, contrast plain and nasal glottalised clicks, but in languages without such a contrast, the glottalised click is nasal. Miller (2011) analyses the glottalisation as phonation, and so considers these to be simple clicks.
Various languages also have prenasalised clicks, which may be analysed as consonant sequences.Sotho, for example, allows a syllabic nasal before its three clicks, as innnqane 'the other side' (prenasalised nasal) andseqhenqha 'hunk'.
There is ongoing discussion as to how the distinction between what were historically described as 'velar' and 'uvular' clicks is best described. The 'uvular' clicks are only found in some languages, and have an extended pronunciation that suggests that they are more complex than the simple ('velar') clicks, which are found in all. Nakagawa (1996) describes the extended clicks inGǀwi asconsonant clusters, sequences equivalent to Englishst orpl, whereas Miller (2011) analyses similar sounds in several languages as click–non-clickcontours, where a click transitions into a pulmonic or ejective articulation within a single segment, analogous to how Englishch andj transition from occlusive to fricative but still behave as unitary sounds. With ejective clicks, for example, Miller finds that although the ejective release follows the click release, it is the rear closure of the click that is ejective, not an independently articulated consonant. That is, in a simple click, the release of the rear articulation is not audible, whereas in a contour click, the rear (uvular) articulation is audibly released after the front (click) articulation, resulting in a double release.
These contour clicks may belinguo-pulmonic, that is, they may transition from a click (lingual) articulation to a normal pulmonic consonant like[ɢ] (e.g.[ǀ͡ɢ]); orlinguo-glottalic and transition from lingual to an ejective consonant like[qʼ] (e.g.[ǀ͡qʼ]): that is, a sequence of ingressive (lingual) release + egressive (pulmonic or glottalic) release. In some cases there is a shift in place of articulation as well, and instead of a uvular release, the uvular click transitions to a velar orepiglottal release (depending on the description,[ǂ͡kxʼ] or[ǂᴴ]). Althoughhomorganic[ǂ͡χʼ] does not contrast with heterorganic[ǂ͡kxʼ] in any known language, they are phonetically quite distinct (Miller 2011).
Implosive clicks, i.e. velar[ɠ͡ʘɠ͡ǀɠ͡ǃɠ͡ǂɠ͡ǁ], uvular[ʛ͡ʘʛ͡ǀʛ͡ǃʛ͡ǂʛ͡ǁ], andde facto front-closed palatal[ʄ͡ʘʄ͡ǀʄ͡ǃʄ͡ǁ] are not only possible but easier to produce than modally voiced clicks. However, they are not attested in any language.[23]
The 'Khoisan' languages, as well as Bantu Yeyi, have glottalized nasal clicks. Contour clicks are restricted to southern Africa, but are very common there: they are found in all members of the Tuu, Kxʼa and Khoe families, as well as in the Bantu language Yeyi.
In a comparative study of clicks across various languages, using her own field work as well as phonetic descriptions and data by other field researchers, Miller (2011) posits 21 types of clicks that contrast in manner or airstream.[note 4] Thehomorganic and heterorganic affricated ejective clicks do not contrast in any known language, but are judged dissimilar enough to keep separate. Miller's conclusions differ from those of the primary researcher of a language; see the individual languages for details.
Taa (ǃXóõ) andNǁng (Nǀuu) areTuu languages, from the two branches of that family.
Each language below is illustrated with Ʞ as a placeholder for the different click types. Under each language are the orthography (in italics, with old forms in parentheses), the researchers' transcription (in⟨angle brackets⟩), or allophonic variation (in [brackets]). Some languages also have labialised or prenasalised clicks in addition to those listed below.
Yeyi also has prenasalised/ŋᶢꞰ/. The original researchers believe that[Ʞʰ] and[Ʞχ] are allophones.
A DoBeS (2008) study of the Western ǃXoo dialect of Taa found several new manners: creaky voiced (the voiced equivalent of glottalised oral), breathy-voiced nasal, prenasalised glottalised (the voiced equivalent of glottalised) and a (pre)voiced ejective. These extra voiced clicks reflect Western ǃXoo morphology, where many nouns form their plural by voicing their initial consonant. DoBeS analyses most Taa clicks as clusters, leaving nine basic manners (marked with asterisks in the table). This comes close to Miller's distinction between simple and contour clicks, shaded light and medium grey in the table.
Languages of the southern African Khoisan families only permit clicks at the beginning of a word root. However, they also restrict other classes of consonant, such asejectives andaffricates, to root-initial position. The Bantu languages, Hadza and Sandawe allow clicks within roots.
In some languages, all click consonants within known roots are the same phoneme, as in Hadzacikiringcingca/ǀikiɺiN.ǀiN.ǀa/ 'pinkie finger', which has threetenuis dental clicks. Other languages are known to have the occasional root with different clicks, as in Xhosaugqwanxa/uᶢ̊ǃʱʷaᵑǁa/ 'black ironwood', which has a slack-voiced alveolar click and anasal lateral click.
No natural language allows clicks at the ends of syllables or words, but then no languages with clicks allows many consonants at all in those positions. Similarly, clicks are not found in underlying consonant clusters apart from /Cw/ (and, depending on the analysis, /Cχ/), as languages with clicks do not have other consonant clusters than that. Due to vowelelision, however, there are cases where clicks are pronounced in cross-linguistically common types of consonant clusters, such as Xhosa[sᵑǃɔɓilɛ]Snqobile, fromSinqobile (a name), and[isǁʰɔsa]isXhosa, fromisiXhosa (the Xhosa language).[26]
Like other articulatorily complex consonants, clicks tend to be found inlexical words rather than ingrammatical words, but this is only a tendency. InNǁng, for example, there are two sets ofpersonal pronouns, a full one without clicks and a partial set with clicks (ńg 'I',á 'thou',í 'we all',ú 'you', vs.nǀǹg 'I',gǀà 'thou',gǀì 'we all',gǀù 'you'), as well as other grammatical words with clicks such asǁu 'not' andnǀa 'with, and'.
The shape of the tongue in Nama when articulating an alveolar click (blue) and a palatal click (red) [throat to the right]. The articulation of the vowel[i] is slightly forward of the red line, with its peak coinciding with the dip of the blue line.
In several languages, includingNama andJuǀʼhoan, the alveolar click types[ǃ] and[ǁ] only occur, or preferentially occur, beforeback vowels, whereas the dental and palatal clicks occur before any vowel. The effect is most noticeable with the high front vowel[i]. In Nama, for example, the diphthong[əi] is common but[i] is rare after alveolar clicks, whereas the opposite is true after dental and palatal clicks. This is a common effect ofuvular or uvularised consonants on vowels in both click and non-click languages. InTaa, for example, the back-vowel constraint is triggered by both alveolar clicks and uvular stops, but not by palatal clicks or velar stops: sequences such as*/ǃi/ and*/qi/ are rare to non-existent, whereas sequences such as/ǂi/ and/ki/ are common. The back-vowel constraint is also triggered by labial clicks, though not by labial stops. Clicks subject to this constraint involve a sharpretraction of the tongue during release.
Miller and colleagues (2003) usedultrasound imaging to show that the rear articulation of the alveolar clicks ([ǃ]) in Nama is substantially different from that of palatal and dental clicks. Specifically, the shape of the body of the tongue in palatal clicks is very similar to that of the vowel[i], and involves the same tongue muscles, so that sequences such as[ǂi] involved a simple and quick transition. The rear articulation of the alveolar clicks, however, is several centimetres further back, and involves a different set of muscles in the uvular region. The part of the tongue required to approach the palate for the vowel[i] is deeply retracted in[ǃ], as it lies at the bottom of the air pocket used to create the vacuum required for click airstream. This makes the transition required for[ǃi] much more complex and the timing more difficult than the shallower and more forward tongue position of the palatal clicks. Consequently,[ǃi] takes 50ms longer to pronounce than[ǂi], the same amount of time required to pronounce[ǃəi].
Languages do not all behave alike. InNǀuu, the simple clicks/ʘ,ǃ,ǁ/ trigger the[əi] and[æ] allophones of/i/ and/e/, whereas/ǀ,ǂ/ do not. All of the affricated contour clicks, such as/ǂ͡χ/, do as well, as do the uvular stops/q,χ/. However, the occlusive contour clicks pattern like the simple clicks, and/ǂ͡q/ does not trigger the back-vowel constraint. This is because they involve tongue-root raising rather thantongue-root retraction in the uvular-pharyngeal region. However, inGǀwi, which is otherwise largely similar, both/ǂ͡q/ and/ǂ͡χ/ trigger the back-vowel constraint (Miller 2009).
One genetic study concluded that clicks, which occur in the languages of the genetically divergent populations Hadza and !Kung, may be an ancient element of human language.[27] However, this conclusion relies on several dubious assumptions (seeHadza language), and most linguists[citation needed] assume that clicks, being quite complex consonants, arose relatively late in human history. How they arose is not known, but it is generally assumed that they developed from sequences of non-click consonants, as they are found allophonically fordoubly articulated consonants in West Africa,[28] for/tk/ sequences that overlap at word boundaries in German,[10] and for the sequence/mw/ inNdau andTonga.[note 11] Such developments have also been posited in historical reconstruction. For example, theSandawe word for 'horn',/tɬana/, with a lateral affricate, may be a cognate with the root/ᵑǁaː/ found throughout theKhoe family, which has a lateral click. This and other words suggests that at least some Khoe clicks may have formed from consonant clusters when the first vowel of a word was lost; in this instance *[tɬana] > *[tɬna] >[ǁŋa]~[ᵑǁa].
On the other side of the equation, several non-endangered languages in vigorous use demonstrate click loss. For example, theEast Kalahari languages have lost clicks from a large percentage of their vocabulary, presumably due toBantu influence. As a rule, a click is replaced by a consonant with close to themanner of articulation of the click and theplace of articulation of the forward release: alveolar click releases (the[ǃ] family) tend to mutate into a velar stop or affricate, such as[k],[ɡ],[ŋ],[k͡x]; palatal clicks (the[ǂ] family) tend to mutate into a palatal stop such as[c],[ɟ],[ɲ],[cʼ], or a post-alveolar affricate[tʃ],[dʒ]; and dental clicks (the[ǀ] family) tend to mutate into an alveolar affricate[ts].[citation needed]
Clicks are often presented as difficult sounds to articulate within words. However, children acquire them readily; a two-year-old, for example, may be able to pronounce a word with a lateral click[ǁ] with no problem, but still be unable to pronounce[s].[29]Lucy Lloyd reported that after long contact with the Khoi and San, it was difficult for her to refrain from using clicks when speaking English.[30]
^This is the case for all clicks used as consonants in words. Paralinguistically, however, there are other methods of making clicks:under the tongue or as above but by releasing the rear occlusion first. See#Places of articulation.
^Exceptions occurs in words borrowed from Bantu languages, which may have click in the middle.
^⟨⦀⟩ (a triple pipe) in Doke (1954) and Cole (1966) is anad hoc phonetic pipe letter for Doke's orthographic click letter⟨ψ⟩.
^Not counting the egressive "spurt" in Damin, and three additional voiced manners in Western ǃXoo, which pair up with voiceless manners.
^Ekoka ǃKung has an additional manner,ˀᵑꞰ. Grootfontein and Mangetti Dune ǃKung, on the other hand, have a substantially smaller inventory:ᵏꞰ,ᶢꞰ,Ʞʰ,ᵑꞰ,ᵑ̊Ʞʱ,ᵑꞰˀ,Ʞ͡χ,Ʞ͡kxʼ.
^Perhaps better described asslack voice. Tone-depressor effect.[24]
^Tone-depressor effect. Sometimes a prenasalized click with a short, voiced oral occlusion, but usually without.
^Not technically a click, but the only other attested sound with a lingual airstream mechanism.
^Here the labial[m] may have assimilated to the velar place of the[w], as[m͡ŋw], with the release of the labial before the velar later generating a click[ᵐʘw]
^Instead of a tie bar, a superscript velar or uvular letter is sometimes seen: ⟨ᵏǂᶢǂᵑǂ𐞥ǂ⟩ etc.
^This can be convenient, as different authorities call the ǂ-clicks different things, so while it is unambiguous to call them "ǂ-clicks", it can be confusing to refer to them with terms like 'palatal', 'palato-alveolar' or 'alveolar', all of which have been used for both the sharp, flat-sounding ǂ-clicks and for the hollow-sounding ǃ-clicks.
^Nurse, Derek; Philippson, Gérard (2003).The Bantu languages. pp. 31–32.
^Hale, Ken; Nash, David (1997)."Damin and Lardil Phonotactics"(PDF). In Tryon, Darrell; Walsh, Michael (eds.).Boundary Rider: Essays in Honour of Geoffrey O'Grady. Canberra: Pacific Linguistics, ANU. pp. 247–259.
^Gunnink, Hilde (2023). "The adoption and proliferation of clicks in Bantu languages: the role ofhlonipha revisited".South African Journal of African Languages.43 (3):216–225.doi:10.1080/02572117.2023.2294412.
^abFuchs, Susanne; Koenig, Laura; Winkler, Ralf (2007).Weak clicks in German?(PDF). Proceedings of the 16th International Congress of Phonetic Sciences. Saarbrücken. pp. 449–452.Archived(PDF) from the original on 24 July 2011. Retrieved16 May 2011.
^Nathan, Geoffrey (2001). "Clicks in a Chinese Nursery Rhyme".Journal of the International Phonetic Association.31 (2):223–228.doi:10.1017/S0025100301002043.
^Doke, Clement M. (1969) [1926].The phonetics of the Zulu language. Johannesburg: University of the Witwatersrand Press.
^Beach, Douglas Martyn (1938).The phonetics of the Hottentot language. W. Heffer & sons.
^Click releases are not in themselves consonants (segments). To transcribe a click consonant, a second IPA letter is needed for the rear place of articulation, as in ⟨k͡ǂ⟩ or ⟨ǂ͡qχʼ⟩
^Grenoble, Lenore (2014). "Verbal gestures: Toward a field-based approach to language description". In Plungian (ed.).Язык, константы, переменные : памяти Александра Евгеньевича Кибрика [Language. Constants. Variables: In memory of A. E. Kibrik]. Saint Petersburg: Aleteija. pp. 105–118.ISBN978-5-906705-14-3.
^Miller, Amanda (2011). "The Representation of Clicks".The Blackwell Companion to Phonology.
^Bleek, Wilhelm (1862).A Comparative Grammar of South African Languages. Vol. 1. pp. 12–13.
^Miller; Brugman; Sands; Namaseb; Exter; Collins (2009). "Differences in airstream and posterior place of articulation among Nǀuu clicks".Journal of the International Phonetic Association.39 (2):129–161.doi:10.1017/S0025100309003867.
^Pike, Kenneth (1972). Brend, Ruth (ed.).Selected Writings: To Commemorate the 60th Birthday of Kenneth Lee Pike. p. 226.
^Jessen; Roux (2002). "Voice quality differences associated with stops and clicks in Xhosa".Journal of Phonetics.30 (1):1–52.doi:10.1006/jpho.2001.0150.
^According toNurse & Philippson (2003, p. 616). This is typically transcribed as a prenasalized click, and is not included in Miller.
^Bennett, William (2020). "Click Phonology". In Sands, Bonny (ed.).Click Consonants. Brill. pp. 115–116.
Ladefoged, Peter (1968).A phonetic study of West African languages: An auditory-instrumental survey (2nd ed.). Cambridge University Press.ISBN0-521-06963-7.
Miller, Amanda; Namaseb, Levi; Iskarous, Khalil (2003).Tongue Body constriction differences in click types.
Miller, Amanda (2011). "The Representation of Clicks". In Oostendorp (ed.).The Blackwell Companion to Phonology.
Traill, Anthony; Vossen, Rainer (1997). "Sound change in the Khoisan languages: new data on click loss and click replacement".J African Languages and Linguistics.18 (1):21–56.doi:10.1515/jall.1997.18.1.21.