noun, feminine

diphtongaison

/dif.tɔ̃.ɡɛ.zɔ̃/

noun, feminine/dif.tɔ̃.ɡɛ.zɔ̃/plural: diphtongaisons

diphthongization

From diphtongue + -aison.

diphtongaison — French Dictionary | Passage