Pronunciation: Brit. /ˌɒnəmatəˈpiːə/ , U.S. /ˈˌɑnəˌmɑdəˈpiə/ ,
/ˈˌɑnəˌmædəˈpiə/ Inflections: Plural onomatopoeias, unchanged.
Etymology: < classical Latin onomatopoeia the making of words <
Hellenistic Greek ὀνοματοποιία < ancient Greek ὀνοματο- onomato- comb.
form + -ποιία -poeia comb. form. Compare Middle French, French
onomatopée imitative formation of a word (1585), a word formed in this
way (1768; 1665 as omomatopeia : compare sense 1b), Italian onomatopea
(1560; a1498 as onomatopia), Old Occitan onomothopeya (c1330), Spanish
onomatopeya (1450 as onomatopeia).
N.E.D. (1903) gives the
pronunciation as (onǫ:mătopī·yă, ǫ:nŏmă-) /əʊˌnɒmətəʊˈpiːjə/
First use in English was:
1553 T. Wilson Arte of Rhetorique iii. f. 92v, A worde makinge
called of the Grecians Onomatopeia is when we make wordes of oure owne
mynde, suche as be deriued from the nature of thinges.
They don't give any pronunciation history farther back than 1903.
It's instructive that Late Latin and the Romance languages usually pronounced this word's ending with an /e/ instead of an /i/:
- Latin onomatopoeia /-peia/ from earlier /-pojia/
- French onomatopée /-pe:/
- Italian onomatopea /-pea/ but also onomatopia /-pia/
- Old Occitan onomothopeya /-peja/
- Spanish onomatopeya & onomatopeia /-peja/
While the Greek underwent a vowel shift of the ending to Modern Greek /-pi'ía/. This reminded me of English's own Great Vowel Shift (GVS). If the first use in English was as far back as 1553, then the vowel may have been subject to the GVS. In particular:
Middle English [ɛː] raised to [eː] and then to modern English [iː] (as
Middle English [eː] raised to Modern English [iː] (as in
The above would result in an original /-peja/ becoming the modern /pija/. So, it seems possible that the original English borrowing from Latin/Greek had an /e/ and that it has changed to /i/ since then.
This is detective work and reasoning, not citation, so take it for what it's worth.