$ sudo apt-get remove libckit-smlnj 

Uninstall libckit-smlnj including dependent package

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

$ sudo apt-get remove --auto-remove libckit-smlnj 

Use Purging libckit-smlnj

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

$ sudo apt-get purge libckit-smlnj 

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 libckit-smlnj 

See Also,