$ sudo apt-get remove munin-node 

Uninstall munin-node including dependent package

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

$ sudo apt-get remove --auto-remove munin-node 

Use Purging munin-node

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

$ sudo apt-get purge munin-node 

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 munin-node 

See Also,