David Bowie’s son didn’t like Lady Gaga’s Grammys tribute Duncan Jones described the performance as “mentally confused” and “irrational.”

Lady Gaga gave it her all during her David Bowie tribute at the Grammys last night,serving up a medley of classics like “Space Oddity”, “Changes”, and “Ziggy Stardust” under the guise of several Bowie personas. The monster affair didn’t leave everyone impressed, however.

Shortly after wrapping up her performance, Bowie’s son Duncan Jones took to Twitter to express his distaste for the whole thing. As a double slam to the ARTPOP singer, Jones used the Oxford dictionary definition for “gaga” to describe the tribute: “‘overexcited or irrational, typically as a result of infatuation or excessive enthusiasm; mentally confused.” Ouch.

“overexcited or irrational, typically as a result of infatuation or excessive enthusiasm; mentally confused.” Damn it! What IS that word!?

— Duncan Jones (@ManMadeMoon) February 16, 2016