$ sudo apt-get remove lua-cosmo 

Uninstall lua-cosmo including dependent package

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

$ sudo apt-get remove --auto-remove lua-cosmo 

Use Purging lua-cosmo

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

$ sudo apt-get purge lua-cosmo 

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 lua-cosmo 

See Also,