Examples: cartography card archaeology archetype monarchy legal loyal purse personal cinema kinase car carpenter hippopotamus Mesopotamia dative data date
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English diphthong
French diphtongue (derived)
Ancient Greek δίφθογγος (derived)
Ancient Greek δίς (mention)
Ancient Greek φθόγγος (mention)

English diphthongisation (suffix)
English diphthongal (suffix)
English diphthongize (suffix)
English diphthongization (suffix)
English diphthongic (suffix)
English aphthong (mention)
English diphthongation (suffix)
English diphthongoid (suffix)
English diphthongy (suffix)
Esperanto diftongo (borrowed)