Pronunciations
The original pronunciation in Medieval Greek must have been /cýrie eléison xristé eléison/, just when the Byzantine Rite was in force. The same sentence would be pronounced as /ky͜ýri.e elé.ɛ͜ɛson kʰristé elé.ɛ͜ɛson/ in Attic Greek circa 500–300 BC. Although at such a time this sentence was obviously not used, the individual words already existed.
The transliteration of ἐλέησον as "eléison" shows that the non-classical itacist pronunciation of the Greek letter eta (η) is used. Although the Greek words have seven syllables (Ký-ri-e, e-lé-i-son), pronunciations as six syllables (Ký-ri-e, e-léi-son) or five (Ký-rie, e-léi-son) have been used. Text underlay in mediaeval and Renaissance music attests that "Ký-ri-e-léi-son" (five syllables) was the most common setting until perhaps the mid-16th century. William Byrd's mass for 4 voices is a notable example of a musical setting originally written with five syllables in mind, later altered for six syllables.
Mediaeval poetry sometimes has 'Kýrieléis', an even more drastic four-syllable form, used as a convenient rhyme with various words in macaronic poems and songs.
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