One of the biggest moments during Monday night's Grammy Awards was Lady Gaga's over-the-top tribute to David Bowie. Most viewers seemed very impressed with the singer's innovative performance. Billboard called the rapid-fire seven-minute medley of Bowie hits "incredible," while Rolling Stone said it was "astonishing." But not everyone had such kind words for the pop star. Duncan Jones, Bowie's son, tweeted out a thinly veiled dig at Gaga Monday night. He wrote, "'overexcited or irrational, typically as a result of infatuation or excessive enthusiasm; mentally confused.' Damn it! What IS that word!?" Obviously, Jones was citing the dictionary definition of "gaga" from a not-so-flattering angle. There's a strong possibility that Jones, like some other viewers, was unhappy about Gaga's collaboration with Intel. But even Gaga wouldn't argue with the assertion that she's infatuated with the late icon. Before Monday's show, Gaga got a tattoo of Bowie's face on her midsection. She also shared a video of herself crying while getting her makeup done. Whether you loved it or hated it, it's hard to argue that Gaga didn't give it her all. Below, Jones' tweet, plus some more of the positive and negative reactions to the tribute.