Fronting_(sound_change)
Fronting (sound change)
Sound changes
In phonology, fronting or less commonly advancing is a sound change in which a vowel or consonant becomes fronted or pronounced farther to the front of the vocal tract than some reference point. The opposite situation, in which a sound becomes pronounced farther to the back of the vocal tract, is called backing or retraction. Fronting may be triggered by a nearby sound, in which case it is a form of assimilation, or may occur on its own.