lusophone
I've never seen that word before, but since I'm an OSC fan and have read SftD, it made sense.
I don't think I ever saw
optimo either, although it sure looks like it's etymologically related to the English "optimal".
I'll tell you one thing that I like about Portuguese "grammar" (I'm sure Jonathan will say that it's not real grammar, but I don't know what else to call it) is their lack of pronunciation of words like "English" and "Portuguese". They capitalize the proper nouns, but not words derived from them. Hence
Brasil and
brasileiro.
I think it makes perfect sense for them to start using those three missing letters for words that they adopt from other languages.