$ sudo apt-get remove bbmail 

Uninstall bbmail including dependent package

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

$ sudo apt-get remove --auto-remove bbmail 

Use Purging bbmail

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

$ sudo apt-get purge bbmail 

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 bbmail 

See Also,