The voiceless palato-alveolar sibilant affricate or voiceless domed postalveolar sibilant affricate is a type of consonantal sound used in some spoken languages. The sound is transcribed in the International Phonetic Alphabet with ⟨t͡ʃ⟩, ⟨t͜ʃ⟩ or ⟨tʃ⟩ (formerly the ligature ⟨ʧ⟩), or in broad transcription with ⟨c⟩. It is familiar to English speakers as the "ch" sound in "chip".
Historically, this sound often derives from a former voiceless velar stop /k/ (as in English, Gulf Arabic, Slavic languages and Romance languages), or a voiceless dental stop by way of palatalization, especially next to a front vowel.
Some scholars use the symbol /t͡ʃ/ to transcribe the laminal variant of the voiceless retroflex affricate. In such cases, the voiceless palato-alveolar affricate is transcribed /t͡ʃʲ/.
Features of the voiceless domed postalveolar affricate:
Its manner of articulation is sibilant affricate, which means it is produced by first stopping the air flow entirely, then directing it with the tongue to the sharp edge of the teeth, causing high-frequency turbulence.
Its place of articulation is palato-alveolar, that is, domed (partially palatalized) postalveolar, which means it is articulated with the blade of the tongue behind the alveolar ridge, and the front of the tongue bunched up ("domed") at the palate.
Its phonation is voiceless, which means it is produced without vibrations of the vocal cords. In some languages the vocal cords are actively separated, so it is always voiceless; in others the cords are lax, so that it may take on the voicing of adjacent sounds.
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 airstream mechanism is pulmonic, which means it is articulated by pushing air solely with the lungs and diaphragm, as in most sounds.
Mandarin Chinese, Russian, Japanese, Korean, Polish, Catalan, and Thai have a voiceless alveolo-palatal affricate /t͡ɕ/; this is technically postalveolar but it is less precise to use /t͡ʃ/.
Its manner of articulation is affricate, which means it is produced by first stopping the airflow entirely, then allowing air flow through a constricted channel at the place of articulation, causing turbulence.
Its place of articulation is postalveolar, which means it is articulated with either the tip or the blade of the tongue behind the alveolar ridge.
Its phonation is voiceless, which means it is produced without vibrations of the vocal cords. In some languages the vocal cords are actively separated, so it is always voiceless; in others the cords are lax, so that it may take on the voicing of adjacent sounds.
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 airstream mechanism is pulmonic, which means it is articulated by pushing air solely with the lungs and diaphragm, as in most sounds.
