Rationalistic - Please explain the term

Well, he is a real person. Whether he is an empiricist or not I don’t really know. Although I don’t see how that would matter. I guess I was just curious as to whether this was a big deal or not. Because if its not, I guess if someone were to ask me about Ayn Rand (whether its my friend or not), and her philosophy, and how to describe it, I guess it would be ok to call her a rationalist, I mean if the word really can just mean rational then it wouldn’t matter.