That's the moniker Troy Aikman gave the world-famous popstar while broadcasting Monday Night Football ... when cameras showed the singer after her man Travis Kelce made a play for the Chiefs.

After a two-game hiatus, Swift appeared in an Arrowhead Stadium suite to watch her BF and his Chiefs teammates beat the New Orleans Saints, 26-13.

Like many fans, Aikman, Hall of Famer turned MNF color commentator, was seemingly excited to see the "Fortnight" singer back at the game ... and at one point, Troy gave her a shoutout.

Or, revealed an untold secret!

"The Mrs. likes it," Aikman said after Kelce made a catch.

Troy's broadcast partner Joe Buck corrected him, saying ... "You know they're not married, right?"

Aikman apologized, "Oh, I know. I’m sure I’m in trouble for saying that."

Troy obviously meant no harm, but don't be surprised if he hears from the Swifties.

Of course, Travis and Taylor started dating last fall ... and have become the most talked about couple in all sports and entertainment. The inseparable couple has been all over the world together ... and TS even thanked Kelce during a recent MTV award show acceptance speech.