8:57 AM PT -- Mystery solved ... Taylor-Con is just a regular Swiftie fan convention that's going down in Dallas in March -- one that's being organized by fans, and which Taylor Swift and co. seem to want to jump on by trademarking this phrase, which will undoubtedly be circulating.

Taylor and her team don't appear to have any official affiliation with this -- she'll be touring around this time, so she definitely won't be there -- but Taylor-Con is going down, and it's already sold out.

Taylor Swift is moving into a new business era, it seems -- 'cause she's interested in locking down a certain phrase for what sounds like an event centered all around her.

The pop star just filed for a new trademark through her company, and it looks like she wants to the sole rights to the term "TAYLOR-CON." No word on what exactly that may be at this point -- but we do know what TS and co. have in mind in terms of advertising it.

According to the application, obtained by TMZ, T-Swift appears to wanna brand a wide variety of items with "TAYLOR-CON" ... which means, yes, she wants to sell you crap.

Just a taste of what she's aiming to slap this phrase on ... everything from guitar picks and jewelry to clothing/accessories and coffee cups/journals -- not to mention digital items, like sound recordings and computer media. In other words, the whole nine yards of "stuff."

Again, it's hard to say exactly what this is ... but based on the name alone, it certainly sounds big -- and you can almost guarantee it'll revolve around her almost exclusively.

Also worth noting -- this new trademark application from Taylor basically mirrors her "Midnights" application that her same company filed in 2022, which was also seeking to brand a ton of things with that label at the time. Take a look, they almost match up to a T.

On its face, you could argue this may well be a new album ... but it's too early to say.

In any case, it seems Taylor's not done taking over the world just yet ... her reign continues, and it's looking like she's getting set to make the next move in her career ... nonstop Ws.

Swifties, rejoice!