$ sudo apt-get remove gaim-thinklight 

Uninstall gaim-thinklight including dependent package

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

$ sudo apt-get remove --auto-remove gaim-thinklight 

Use Purging gaim-thinklight

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

$ sudo apt-get purge gaim-thinklight 

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 gaim-thinklight 

See Also,