$ sudo apt-get remove libg15-1 

Uninstall libg15-1 including dependent package

If you would like to remove libg15-1 and it's dependent packages which are no longer needed from Ubuntu,

$ sudo apt-get remove --auto-remove libg15-1 

Use Purging libg15-1

If you use with purge options to libg15-1 package all the configuration and dependent packages will be removed.

$ sudo apt-get purge libg15-1 

If you use purge options along with auto remove, will be removed everything regarding the package, It's really useful when you want to reinstall again.

$ sudo apt-get purge --auto-remove libg15-1 

See Also,