Final-obstruent devoicing

Final-obstruent devoicing or terminal devoicing is a systematic phonological process occurring in languages such as Catalan, German, Dutch, Breton, Russian, Turkish, and Wolof. In such languages, voiced obstruents become voiceless before voiceless consonants and in pausa.

In Dutch and Afrikaans, terminal devoicing results in homophones such as hard 'hard' and hart 'heart' as well as differences in consonant sounds between the singular and plural forms of nouns, for example golf–golven (Dutch) and golf–golwe (Afrikaans) for 'wave–waves'.

The history of the devoicing phenomenon within the West Germanic languages is not entirely clear, but the discovery of a runic inscription from the early fifth century suggests that this terminal devoicing originated in Frankish. Of the old West Germanic languages, Old Dutch, a descendant of Frankish, is the earliest to show any kind of devoicing, and final devoicing also occurred in Frankish-influenced Old French.

English does not have phonological final-obstruent devoicing of the type that neutralizes phonemic contrasts; thus pairs like bad and bat are distinct in all major accents of English. Nevertheless, voiced obstruents are devoiced to some extent in final position in English, especially when phrase-final or when followed by a voiceless consonant (for example, bad cat [bæd̥ kʰæt]).

Relics of a final devoicing of "v" are to be found between words so related as "half" and "halves", and "knife" and "knives" distinguishing singular and plural.

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