Is factoid an Auto-antonym?

Question

I had thought factoid meant "a brief or trivial item of news or information"

But now I googled the meaning and it says,

In most examples of janus words online the meanings are quite exactly opposite. In this case I was not 100% sure. The opposite of a fact or news is an untruth. So since the alternative meaning is only unreliable news and not reliable untruth. Is this not a janus word? what do you all think?

---

factoid

/ˈfaktɔɪd/

noun

1. an item of unreliable information that is reported and repeated so often that it becomes accepted as fact.

"he addresses the facts and factoids which have buttressed the film's legend"

NORTH AMERICAN

2. a brief or trivial item of news or information.

"how does the brain retain factoids that you remember from a history test at school?"

I did not find it in this list.

Answer 1

The answer is no, it is not a Janus word. The reason is simply that its two accepted meanings are not antonymous at all.

As for those meanings and their accepted usage, the American Heritage usage panel says this:

The suffix -oid normally means "resembling, having the appearance of." Thus, factoid originally referred to a claim that appears reliable or accurate, often because it has been repeated so frequently that people assume it is true. The word still has this meaning for many writers and readers; in our 2013 survey, 59 percent of the Usage Panel accepted it in the sentence The editorial writer relied on numerous factoids that have long been discredited. But factoid is also often used to mean a brief, somewhat interesting fact, and this sense has become common in recent decades. Some 64 percent of the Panel accepted this usage in the sentence Each issue of the magazine begins with a list of factoids, like how many pounds of hamburger were consumed in Texas last month. As the ballot results indicate, neither usage is overwhelmingly approved. If you use the word factoid, be sure the sentence makes it clear whether you are referring to a spurious claim, on the one hand, or an isolated, trivial, or mildly intriguing fact, on the other.

And as for the term's etymology, Farlex says this:

Coined by the novelist Norman Mailer from fact + -oid (as in android, humanoid), in reference to his fictionalized biography of Marilyn Monroe.