Fricative

A fricative is a consonant produced by forcing air through a narrow channel made by placing two articulators close together.

Sound Changes

To

Fricatives usually develop from plosives under the following conditions:

• / #_C in Avestan
• / _# in Gothic
• / V_V in Irish

When a language distinguishes aspirated and unaspirated plosives, either series might become a fricative (the former occured in Greek, the later in Germanic).