There's no internal spell checker in C5 that i know of, but if you use a web browser such as Firefox, or Chrome they have built in spell checkers. That way you are able to spell check everywhere on the web. :)

TinyMCE does, and c5 has a library that addons can use

Yes but it's not something that is set up to function "out of the box", plus it is only limited to TinyMCE instances and not other inputs and textareas. Using a spell checker within your browser is not limited to the C5 install and the WYSIWYG's there in. It also doesn't required any user interaction in order to work.

Thanks for the response. I was instructed to go to Rich Text Editor and select "Office" and clear the cache. That worked and I now have a spell checker working on my site.