The "7 Rings" pop star was rollin' deep Thursday night as she was leaving Nobu in Malibu ... where she, along with friends and family, celebrated the release of her new album, "thank u, next."

The highly-anticipated 12-track collection -- her second in the last 6 months -- has been out less than 24 hours and it's already being dubbed a masterpiece and, arguably, her most mature and revealing album to date.

There's a track on it called "Ghostin'" and many fans believe it's about her longing for Mac Miller while she's with Pete Davidson. One of the verses goes, "Though I wish he were here instead. Don't want that living in your head. He just comes to visit me. When I'm dreaming every now and then."

Of course, the first single -- the title track -- became a huge hit when Ariana dropped it back in November. Despite all the success ... Ariana's still dealing with drama over the Grammys.

As we reported ... she called out the show's producer, Ken Ehrlich, for lying about why she's not performing at the Grammys. He said she was too frazzled to pull it together in time for Sunday's broadcast -- but AG called BS, saying Ken stifled her efforts to perform "7 Rings" ... so she said deuces.