Comment by danso

I think it's being argued that describing a name variation as a "misspelling" -- as in, a mistake -- is incorrect. What does the etymology or historical popularity of "Philip" have to do with it? We don't know that he has that name because he truly loves horses or because his parents attempted to honor a king of Macedonia.

I know this is treading into the classic prescriptive vs. descriptive linguistic debate, but the reason why we can call "referer" a misspelling -- rather than a creative decision - is because the original authors seem to admit that it was unintentional. Fewer folks would be calling it a misspelling if the authors had meant to do it, e.g. to avoid a name collision with some other attribute named "referrer" or to honor a colleague named "Referer".