Sound change

Process of language change that affects pronunciation or sound system structure

In historical linguistics, a sound change is a change in the pronunciation of a language. A sound change can involve the replacement of one speech sound by a different one or a more general change to the speech sounds that exist, such as the merger of two sounds or the creation of a new sound. A sound change can eliminate the affected sound, or a new sound can be added. Sound changes can be environmentally conditioned if the change occurs in only some sound environments, and not others.

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