Bilabial nasal click
|Bilabial nasal click|
Features of the bilabial nasal click:
- The airstream mechanism is lingual ingressive (also known as velaric ingressive), which means a pocket of air trapped between two closures is rarefied by a "sucking" action of the tongue, rather than being moved by the glottis or the lungs/diaphragm. The release of the forward closure produces the "click" sound. Voiced and nasal clicks have a simultaneous pulmonic egressive airstream.
- Its place of articulation is bilabial, which means it is articulated with both lips.
- Its phonation is voiced, which means the vocal cords vibrate during the articulation. However, in some languages, such as Swiss German, it can just mean that this consonant is pronounced shorter and weaker than its voiceless counterpart, while its voicedness or lack thereof is not relevant. In such cases it's more accurate to call such sounds lenis or lax.
- It is a nasal consonant, which means air is allowed to escape through the nose, either exclusively (nasal stops) or in addition to through the mouth.
- Because the sound is not produced with airflow over the tongue, the central–lateral dichotomy does not apply.
Bilabial nasal clicks only occur in the Tuu and Kx'a families of southern Africa, in the Australian ritual language Damin, and for /mw/ in some of the languages neighboring Shona, such as at least for some speakers of Ndau and Tonga.
Glottalized bilabial nasal click
bilabial nasal click
The Tuu and Kx'a languages also have glottalized nasal clicks. These are formed by closing the glottis so that the click is pronounced in silence; however, any preceding vowel will be nasalized.