$ sudo apt-get remove libclhep2.1 

Uninstall libclhep2.1 including dependent package

If you would like to remove libclhep2.1 and it's dependent packages which are no longer needed from Ubuntu,

$ sudo apt-get remove --auto-remove libclhep2.1 

Use Purging libclhep2.1

If you use with purge options to libclhep2.1 package all the configuration and dependent packages will be removed.

$ sudo apt-get purge libclhep2.1 

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 libclhep2.1 

See Also,