Diaeresis (prosody)

In poetic meter, diaeresis (/daɪˈɛrᵻsɪs/ or /daɪˈɪərᵻsɪs/, also spelled diæresis or dieresis) has two meanings: the separate pronunciation of the two vowels in a diphthong for the sake of meter, and a division between feet that corresponds to the division between words.

Synaeresis, the pronunciation of two vowels as a diphthong (or as a long vowel), is the opposite of the first definition.

Diaeresis comes from the Ancient Greek noun diaíresis (διαίρεσις) "taking apart" or "division" (also "distinction"), from the verb diairéō (διαιρέω) "take apart", a compound of the verb airéō (αἱρέω) "take" and the preposition diá (διά) "through" (in compounds, "apart").

In the phonology of Standard French, the letters ie are normally pronounced [je] or [jɛ] except after Cr or Cl, when they indicate two syllables, [ije] or [ijɛ]. (That exception came into the language only around the 17th century, as can be seen in poems before then.)

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