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-ez Suffix "saying"
Even in Latin the suffix had already fossilized, it was last productive in Proto-Italic. From Latin *-dex 'id.' From Proto-Italic *-dik- 'id.' From Proto-Indo-European *-di̯ḱ- 'id.' From the root *dei̯ḱ- "to say" (whence decir).
Indo-European
Romance
Asturian -áu, Portuguese -ado, Catalan -at, French , Italian -ato
Italic
Oscan -díss, Marrucinian -dix, Marsian -dis, Paelignian -dix, Volscian -dix
Germanic
Gothic ga-teihan "to indicate"
Hellenic
Ancient Greek δείκνῡμι (deíknymi) "to show"
Indo-Iranian
Sanskrit diś- "to show"
-eza Abstract noun-forming suffix.
From Latin -itia 'id.,' via re-interpretation of -itas, a noun-forming suffix indicating a state of being (see -edad, -idad).