Don't just look at the title of the update. Follow the link and look at all affected software. It's very likely that Word was affected by some update to Outlook as well.
I just went through this yesterday. I have Office 2007 installed and I got an update for Office 2003. The update affects all Office 2003 programs including the web components that I actually do have installed. So while I don't have Office 2003 proper installed, I do have part of it installed.