factoid
A dubious bit of “fact,” or a small fact.
Factoid first meant a claim that looks like a fact but is shaky. It now also means a small, isolated fact. If you mean a scrap of trivia, factoid will be read that way. If you mean a false fact, say so: a dubious claim, a made-up statistic.
Examples
Usea factoid with no source
Usea small fact