It was invented as a comically long fake word, but gained enough currency to be used in real writing, though in a tongue-in-cheek way. It's a Latin calque. I'm

It was invented as a comically long fake word, but gained enough currency to be used in real writing, though in a tongue-in-cheek way. It's a Latin calque. I'm sure the spelling should be floccipaucinihil... from pauci, few and nihil, nothing - you and the reviewer have used spellings that differ from this and from each other, but I doubt O'Brian did.