Words ending with “oid” often have their root in the Latinized form of the Greek -oeides, from eidos meaning form and so the suffix is used to suggest that something is like something else but isn’t actually the thing itself. Viz: ovoid means egglike, android mean manlike, humanoid means like a human. There are lots of examples in medicine and science: opioid, cannabinoid, haemorrhoid, paraboloid etc etc. Then, there’s factoid…
…now that’s a funny one. Most people use the word factoid to mean a neat little fact, but that would be factette, surely from the French-derived suffix “ette”, which feminizes a noun, the rather sexist implication being that an “ette” is smaller than the full-sized item. As in kitchenette (small kitchen), serviette (a napkin rather than a tablecloth), launderette (a small laundry) etc.
But…factoid means “like a fact” more precisely, something that is like a fact has only the appearance of a fact, it’s not a fact, it’s often Deceived Wisdom, Things like being able to see the Great Wall of China from the Moon (you cannot), Al Gore claiming to have invented the Internet (he never did make that claim) or that one about Apple Macs never getting viruses (yeah, right, Mr Jobs).
I doubt any of this will stick and it’s why I didn’t call my book Factoids, it would’ve been confusing. The fact that factoid means “like a fact and not actually a fact” and should more correctly be called a factette will remain the archetypal self-referring factoid…