Synizesis

Synizesis (/ˌsɪnəˈziːsɪs/) is a sound change (metaplasm) in which two originally syllabic vowels are pronounced as a single syllable without change in writing. In Latin and Greek, the reason was often to preserve meter, but similar changes can occur naturally.

A tie may be used to represent this pronunciation: dē͡hinc (i.e., deinc).

Homer:

Vergil's Aeneid:

Synizesis comes from the Greek συνίζησις "a sitting together" from σύν "with" and ἵζω "I sit".

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