How to uninstall lilypond-data from Ubuntu
To uninstall just lilypond-data package itself from Ubuntu execute on terminal:
sudo apt-get remove lilypond-data
Uninstall lilypond-data and it's dependent packages
To uninstall the lilypond-data package and any other dependant package which are no longer needed on Ubuntu.
sudo apt-get autoremove lilypond-data
If you also want to delete configuration and/or data files of lilypond-data from Ubuntu then this will work:
sudo apt-get purge lilypond-data
To delete configuration and/or data files of lilypond-data and it's dependencies from Ubuntu then execute:
sudo apt-get autoremove --purge lilypond-data
lilypond-data package information
LilyPond music typesetter (data files)
More information about apt-get remove
apt-get remove is identical to install except that packages are removed instead of installed. Note that removing a package leaves its configuration files on the system. If a plus sign is appended to the package name (with no intervening space), the identified package will be installed instead of removed.