I’ve received some criticism related to my book (Literally, the Best Language Book Ever) for my tendency toward prescriptivism, and we’ve also had some negative comments on the blog for the same reason, but the “word” factoid probably explains the need for rules and consistency in language as well anything.
Factoid is not included in any print dictionary we own, but it is defined in many online dictionaries, including dictionary.com, where it means either an insignificant fact or something fictitious or unsubstantiated that’s presented as fact.
In other words, factoid means either fact or fiction, rendering the term an instant source of confusion. The person saying it, or the person hearing it, can rightfully interpret the word in two opposing ways.
So much for the prescriptivist philosophy of “all that matters is that listener knows what the speaker means.”