a whitelabel is basically a copy of a website made to look like it's part of your network (your sites etc..). Using your logo, color scheme etc.. Made to look like the product you are selling on the whitelabel is/are yours.
for exapmle, one of my blogs at
http://www.slutty8teen.com, I had a whitelabel made for it with
http://www.topbucks.com. The whitelabel is at
http://mobile.slutty8teen.com. The logo used has the same colors as the main site and also the same name so to a surfer it looks like YOUR product.
Not sure if that answered your question, but I'm tired and have a bad headache. It's what I came up with in my crappy state of mind. haha