$ sudo apt-get remove libgconf2.0-cil 

Uninstall libgconf2.0-cil including dependent package

If you would like to remove libgconf2.0-cil and it's dependent packages which are no longer needed from Ubuntu,

$ sudo apt-get remove --auto-remove libgconf2.0-cil 

Use Purging libgconf2.0-cil

If you use with purge options to libgconf2.0-cil package all the configuration and dependent packages will be removed.

$ sudo apt-get purge libgconf2.0-cil 

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 libgconf2.0-cil 

See Also,