The voiceless or more precisely tenuis palatal click is a click consonant found primarily among the languages of southern Africa. The symbol in the International Phonetic Alphabet that represents this sound is ⟨ǂ⟩ (double-barred pipe). A stylistic variant sometimes seen is ⟨⨎⟩ (double-barred esh).
Features of the tenuis palatal 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.