Metaphony
In historical linguistics, metaphony is a class of sound change in which one vowel in a word is influenced by another in a process of assimilation. The sound change is normally "long-distance" in that the vowel triggering the change may be separated from the affected vowel by several consonants, or sometimes even by several syllables.
For more discussion, see the article on vowel harmony.
There are two types:
- Progressive metaphony, in which a vowel towards the beginning of a word influences a subsequent vowel.
- Regressive metaphony, in which a vowel towards the end of the word influences a preceding vowel.
- Vowel harmony is sometimes used synonymously with metaphony. Usually, however, "vowel harmony" refers specifically to a synchronic process operating in a particular language, normally requiring all vowels in a word to agree in a particular feature. Most commonly, the triggering vowel is in the first syllable of the word, as in Turkish, Finnish and Hungarian. In some cases, however, the triggering vowel is in the last syllable, typically a suffix, as in many varieties of Andalusian Spanish.
- Umlaut refers to regressive metaphony, usually specifically of a diachronic type operating in the history of a language. The term "umlaut" is found especially in the Germanic languages. In some other languages, other terms are used instead for the same process.