The hosted domains feature of a website hosting account denotes the number of registered domains which you can include within the same account. Registering a domain name and hosting it are 2 different services although some people consider them to be the exact same thing. While the registration ensures that you become the owner of a certain domain address, the hosting part is what actually allows you to have a web site as this is where your files and emails are going to be. Since these are two different services, you can register a new domain name with one company and host it with another by modifying its name servers (DNS) - the domain shall work in the exact same way just as if it was registered and hosted using the same company. It is also very important to know that changing the hosting means pointing the domain address to an alternative company and not transferring it.