Adele Flashes Engagement Ring During Las Vegas Residency

Adele's bringing the bling to Las Vegas ... singing about everything that seems real and true onstage during her residency -- and, driving fans wild with her giant engagement ring.

The singer-songwriter took the stage at Caesar's Palace's unbelievable concert venue -- the Colosseum -- Friday night ... moving through her regular performance, leaving fans in awe as always.

During the performance of her song, "I Drink Wine," Adele sings the lines "I need some substance in my life, somethin' real / somethin' that feels true" ... and, she couldn't help but put her diamond-clad finger by her head.

The clear implication ... she's got something real in her life now -- and, she wants the whole world to know about it.

Worth noting ...Adele showing her ring isn't a one-off move. In fact, it appears she does it at the same time in each performance -- with very similar choreography.

Of course, Adele announced back in August that she and her superagent beau Rich Paul got engaged ... and, she's clearly deeply in love with her dude -- saying just a few months ago that she wants to have a baby girl with Rich.