Exclude a certain category title from 'the_category'

Hello!

On my posts I display the categories that are assigned to the post with <?php echo the_category(' / ','multiple'); ?>

Now I needed to add an administrative category to avoid displaying certain posts from a ‘featured section’ on my homepage. BUT I don’t want this certain category name to be displayed as a category title on my posts. How to do this? Is it even possible?

Cheers!