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extra- (Prefix) "outside"

18th cent. From the Latin adverb/adjective extra "outside." From exter "outside." From Proto-Italic *eks-ter(o)- 'id.' From Proto-Indo-European *h1éǵhs-tero- 'id.' From *h1éǵh-s "out" and comparative suffix *-tero- (see -tr-).

Romance: Western Vulgar Latin: Portuguese extra-, French extra-, Italian extra-, estra-; Eastern Vulgar Latin: Aromanian strã-, Romanian extra-, stră-

Italic: Oscan ehtrad "outside"

Indo-European: Celtic: Old Irish echtar "without," Middle Welsh eithr 'id.'

Its increasingly frequent use as a prefix led to its exclusive use as a prefix and the loss of it as an independent word.
extrañar (Verb) "to banish;" "to wonder;" "to miss"

11th cent. From Latin extranear 'id.,' from extraneus "foreign," from extra "outside" (see extra- for further etymology).
extraño (Adjective) "strange," "foreign"

12th cent. From Latin extraneus 'id.,' ultimately from extra "outside" (see extra-).
-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).

Romance: Western Vulgar Latin: Asturian -ez, Portuguese -iz, Galician -íz, Catalan -Vtge, French -Vge, Italian -ice

Italic: Oscan -díss, Marrucinian -dix, Marsian -dis, Paelignian -dix, Volscian -dix

Indo-European: 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).