Airstream mechanism

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The airstream mechanism explains how air is used to start speech sounds. It’s one of the key parts of how we talk, along with how the vocal cords vibrate and how the lips and tongue shape sounds. There are three main ways air can be used to start a sound: pulmonic, glottalic, and lingual (velaric).

- Pulmonic (air from the lungs): This is the most common way. The diaphragm and rib cage push air out of the lungs to make sounds. In most languages, the exit of air is outward (egressive). Sometimes air is drawn in (ingressive) for special sounds or interjections, but that’s rare in normal words.

- Glottalic (using the vocal cords): This uses the glottis, the space between the vocal cords, to build pressure or suction.
- Ejectives: you close the glottis, raise the pressure in the mouth, then release. These sounds are usually voiceless.
- Implosives: you raise the glottis to create suction, then lower it, pulling air inward. These are usually voiced.

- Lingual or velaric (two tongue closures): This creates air by moving the tongue while it’s closed at two places (back of the tongue and front of the mouth). The release between the front closures creates a click. Clicks are typically ingressive (air drawn in) and are famous in some southern African languages, though they also occur in other contexts. Some nasal or more complex clicks involve air through the nose or additional releases.

Other sounds can be made without a special airstream at all. These percussive sounds come from one part of the mouth striking another (not common in ordinary speech as phonemes).

Key takeaways:
- The three main airstream mechanisms are pulmonic, glottalic, and lingual.
- Pulmonic sounds use air from the lungs; most sounds are pulmonic egressive.
- Glottalic sounds create ejectives or implosives using the vocal cords.
- Lingual/velaric sounds use two tongue closures to make clicks.
- Some sounds use no airstream at all (percussive), but these are not phonemic in most languages.
- A few languages use ingressive air for special sounds or interjections, but this is rare in everyday speech.