$ sudo apt-get remove kicad 

Uninstall kicad including dependent package

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

$ sudo apt-get remove --auto-remove kicad 

Use Purging kicad

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

$ sudo apt-get purge kicad 

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 kicad 

See Also,