Interfície

It's interesting how "minor" languages can sometimes build new words in a much more sensible way than "big" languages like Portuguese and Spanish. That is probably accounted for by the desire that minority languages have to keep themselves afloat. I just read in Catalan: Durant la seva trajectòria Softcatalà ha traduït projectes com el Netscape, el Firefox, l'entorn GNOME, l'OpenOffice.org, o les primeres versions de la interfície del Google, i ha participat en l'adaptació al català de diverses distribucions de GNU/Linux.

If Portuguese and Spanish speakers had been so ingenious as Catalan, we would have come up with interfície and interficie, respectively and not interface (Portuguese) and interfaz (Spanish), a mere mockery of English interface. Latin facies became ficies in front of prefixes (and inter, as well as super, is one of them). This phenomenon of switching between a's and i's is commonly found in Latin, as with words like deficiente, from Latin deficiens, where the prefix de is appended to the present participle faciens of the verb facere, which became Portuguese fazer and Spanish hacer.