Voiced retroflex click

The voiced retroflex click is a rare click consonant. In practical orthography, an ad hoc symbol ⟨‼⟩ is used for the retroflex clicks; a voiced click with a velar rear articulation is ⟨ɡ͡‼⟩ or ⟨ɡ͜‼⟩, commonly abbreviated to ⟨ɡ‼⟩, ⟨ᶢ‼⟩ or ⟨‼̬⟩. The implicit symbol in the International Phonetic Alphabet is ⟨ɡ͡𝼊⟩ or ⟨ɡ͜𝼊⟩, abbreviated ⟨ɡ𝼊⟩, ⟨ᶢ𝼊⟩ or ⟨𝼊̬⟩.^[1] Linguists who prefer the old IPA letters use the analogous Doke convention^[2] of ⟨ɡ͡ψ⟩ or ⟨ɡ͜ψ⟩, abbreviated ⟨ɡψ⟩, ⟨ᶢψ⟩ or ⟨ψ̬⟩. For a click with a uvular rear articulation, the equivalents are ⟨ɢ͡‼, ɢ͜‼, ɢ‼, 𐞒‼⟩, ⟨ɢ͡𝼊, ɢ͜𝼊, ɢ𝼊, 𐞒𝼊⟩ and ⟨ɢ͡ψ, ɢ͜ψ, ɢψ, 𐞒ψ⟩. Sometimes the accompanying letter comes after the click letter, e.g. ⟨𝼊ɡ⟩ or ⟨𝼊ᶢ⟩; this may be a simple orthographic choice, or it may imply a difference in the relative timing of the releases.^[3]

Features of the voiced retroflex 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 retroflex, which prototypically means it is articulated subapical (with the tip of the tongue curled up), but more generally, it means that it is postalveolar without being palatalized. That is, besides the prototypical subapical articulation, the tongue can be apical (pointed) or, in some fricatives, laminal (flat).
• Its phonation is voiced, which means the vocal cords vibrate during the articulation.
• It is an oral consonant, which means air is allowed to escape through the mouth only.
• It is a central consonant, which means it is produced by directing the airstream along the center of the tongue, rather than to the sides.

The voiced retroflex click is only confirmed from a single language, Central !Kung.^[4]