Diphthongia definitions

Diphthongia

1) Diplophonia
Found on https://www.crosswordclues.com/clue/diphthongia

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diphthongia

(dif-thon´je-ә) the production of double vocal sounds.
Found on http://www.encyclo.co.uk/local/21001

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diphthongia

diplophonia.
Found on https://www.infoplease.com/dictionary/diphthongia

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