It means the name of the website
example:
www.novahq.net is Novahq
http://www.bmfsquad.com/ is Bad Mother ****ers or BMF
http://www.tdi-hq.com/ is THE DUTCH IMMORTALS
So when you put in your information to add your squad into the dfbhd squad links you do what is told. In the "Site Name", you put your name of your squad or the name of the website.
Dude you seriously need to elaborate and give more details when you have a question. No one here knows what the hell you are talking about half the time.