$ sudo apt-get remove gawk 

Uninstall gawk including dependent package

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

$ sudo apt-get remove --auto-remove gawk 

Use Purging gawk

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

$ sudo apt-get purge gawk 

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 gawk 

See Also,