Lady GaGa gags Lady Goo Goo
Lawyers said fans would assume there was an official link between the Paparazzi singer and the nappy-wearing baby.
Lady Goo Goo is one of the characters on Moshi Monsters a website that allows kids to adopt and name creatures.
The singing infant became a YouTube sensation with tunes including one called "Peppy-razzi".
London's High Court ruled that Mind Candy Moshi's British parent firm must not distribute any more Lady Goo Goo tunes.