$ sudo apt-get remove key-mon 

Uninstall key-mon including dependent package

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

$ sudo apt-get remove --auto-remove key-mon 

Use Purging key-mon

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

$ sudo apt-get purge key-mon 

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 key-mon 

See Also,