5.2 The vocal cords
The aperture between the vocal cords is called the glottis: obviously, no air can pass through when the glottis is closed, and when it is open, air can flow through quite freely.
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An Introduction to American English Phonetics Copyright © by Ton Broeders and Carlos Gussenhoven is licensed under a Creative Commons Attribution-NonCommercial-ShareAlike 4.0 International License, except where otherwise noted.