Metaphony (Romance languages)

In the Romance languages, metaphony was an early vowel mutation process that operated in all Romance languages to varying degrees, raising (or sometimes diphthongizing) certain stressed vowels in words with a final /i/ or /u/ or a directly following /j/. This is conceptually similar to the umlaut process so characteristic of the Germanic languages. Metaphony is most extensive in the Italo-Romance languages, and applies to nearly all languages of Italy. However, it is absent from Tuscan, and hence from standard Italian.

Metaphony in the southern Italian languages (those to the south of Tuscany) is triggered by final /i/ and /u/. High-mid vowels /e o/ are raised to /i u/, and low-mid vowels /ɛ ɔ/ are either raised to /e o/ or diphthongized to /je wo/. Metaphony is not triggered by final /o/. The main occurrences of final /i/ are as follows:

The main occurrences of final /o/ are as follows:

The main occurrence of final /u/ is in masculine "count" nouns (< -um).

Metaphony in the northern Italian languages (those to the north of Tuscany) is triggered only by final /i/. In these languages, as in Tuscan, final /u/ was lowered to /o/; it evidently happened prior to the action of metaphony. In these languages, metaphony also tends to apply to final /a/, raising it to /ɛ/ or /e/.

In most Italian languages, most final vowels have become obscured (in the south) or lost (in the north), and the effects of metaphony are often the only markers of masculine vs. feminine and singular vs. plural.

In all of the Western Romance languages, metaphony was triggered by a final /i/ (especially of the first-person singular of the preterite), raising mid-high stressed vowels to high vowels. (It does not normally occur in the nominative plural noun forms in Old French and Old Occitan that have a reflex of nominative plural /i/, suggesting that these developments were removed early by analogy.) Examples:

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