The voiced labial–velar implosive is a rare type of consonantal sound. It occurs in a few African languages, including the Central dialect of Igbo,[1]Lese,[2][3][4] and Ma'di.[5]
Features
Features of the voiced labial–velar implosive:
Its manner of articulation is occlusive, which means it is produced by obstructing airflow in the vocal tract. Since the consonant is also oral, with no nasal outlet, the airflow is blocked entirely, and the consonant is a plosive.
Its place of articulation is labial–velar, which means it is simultaneously articulated with the lips and with the back part of the tongue (the dorsum) against the soft palate (the velum). The dorsal closure is made and released slightly before the labial closure, but they overlap for most of their duration.
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 airstream mechanism is implosive (glottalic ingressive), which means it is produced by pulling air in by pumping the glottis downward. Since it is voiced, the glottis is not completely closed, but allows a pulmonic airstream to escape through it.