Initiation (phonetics)

In phonetics, initiation is the action by which an air-flow is created through the vocal tract. Along with articulation, it is one of the two mandatory aspects of sound production: without initiation, there is no sound. The means of initiating a phone is called its airstream mechanism.Initiation may be divided into pressure and suction. In the former, the organ performing the initiation—called the initiator—builds up pressure within the vocal tract, creating an outward airflow. In the latter, the initiator reduces pressure within the vocal tract, creating an inward airflow.  Phones pronounced with pressure initiation are called egressive, and those pronounced with suction initiation are called ingressive.
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