Are Subtitles for Categories possible?

I have a need to display a subtitle (e.g. a brief description) beneath each category in my WP navigation. The categories are used as the sole navigation for this particular site, so a quick, brief description will be most helpful to the visitors. Upon selecting the category, the archive page then lists the full description.

I thought of placing 2 separate <span>’s in the category description, one for the long and the other for the short and using CSS to display the proper one in it’s respective location…. but WP strips any HTML from the category description field.

I know that subtitles can be achieved on pages/posts using custom fields, but I have not a clue how this can be accomplished with a category.

Any suggestions would be most helpful!
Thanks so much in advance!!