Hide a single category from the side menu

I'm sorry if this question has been asked before but I cannot seem to find the answer anywhere on this forum. I am looking to put some products into a category that is not shown on the side bar menu of my site. I want to link to the category from a picture within another category. I know how to create an image with a link to the categories products but I don't know how to hide the category so that it doesn't show in my sidebar menu. Is there some way of doing this in the css or admin?

Thanks:unsure:

On the page in your admin that lists the categories click on the green icon in the status column. This will turn the category and all of the products in that category off (no way around that) then go into the category and turn the products themselves on